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Document And Entity Information - shares	3 Months Ended
Document And Entity Information - shares	Jul. 31, 2012	Aug. 31, 2012
Document and Entity Information [Abstract]
Entity Registrant Name	Ocean Power Technologies, Inc.
Document Type	10-Q
Current Fiscal Year End Date	--04-30
Entity Common Stock, Shares Outstanding		10,377,621
Amendment Flag	false
Entity Central Index Key	0001378140
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Smaller Reporting Company
Entity Well-known Seasoned Issuer	No
Document Period End Date	Jul. 31, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1

Consolidated Balance Sheets - USD ($)	Jul. 31, 2012	Apr. 30, 2012
Current assets:
Cash and cash equivalents	$ 5,089,657	$ 9,353,460
Marketable securities	23,017,509	22,369,484
Accounts receivable	1,157,791	1,064,796
Unbilled receivables	235,493	223,050
Other current assets	718,270	842,820
Total current assets	30,218,720	33,853,610
Property and equipment, net	880,018	682,933
Patents, net	1,215,248	1,269,457
Restricted cash	1,308,656	1,453,712
Other noncurrent assets	194,618	181,925
Total assets	33,817,260	37,441,637
Current liabilities:
Accounts payable	656,810	440,773
Accrued expenses	3,176,831	2,770,094
Deferred credits payable	600,000	600,000
Unearned revenues	846,422	1,073,389
Current portion of long-term debt	100,000	100,000
Total current liabilities	5,380,063	4,984,256
Long-term debt	325,000	350,000
Total liabilities	5,705,063	5,334,256
Commitments and contingencies (note 9)
Ocean Power Technologies, Inc. Stockholders’ equity:
Common stock, $0.001 par value; authorized 105,000,000 shares, issued 10,405,439 and 10,407,389 shares, respectively	10,405	10,407
Treasury stock, at cost; 27,818 and 23,544 shares, respectively	(111,510)	(102,388)
Additional paid-in capital	158,683,010	158,296,458
Accumulated deficit	(130,325,527)	(125,989,474)
Accumulated other comprehensive loss	(88,413)	(78,990)
Total Ocean Power Technologies, Inc. stockholders’ equity	28,167,965	32,136,013
Noncontrolling interest in Ocean Power Technologies (Australasia) Pty Ltd.	(55,768)	(28,632)
Total equity	28,112,197	32,107,381
Total liabilities and stockholders’ equity	$ 33,817,260	$ 37,441,637

Consolidated Balance Sheets (Parentheticals) - $ / shares	Jul. 31, 2012	Apr. 30, 2012
Preferred stock par value (in Dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock par value (in Dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	105,000,000	105,000,000
Common stock, shares issued	10,405,439	10,407,389
Treasury stock, shares	27,818	23,544

Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
Revenues	$ 982,396	$ 1,910,852
Cost of revenues	979,860	1,901,902
Gross profit	2,536	8,950
Operating expenses:
Product development costs	1,927,427	3,100,587
Selling, general and administrative costs	2,384,338	2,019,742
Total operating expenses	4,311,765	5,120,329
Operating loss	(4,309,229)	(5,111,379)
Interest income, net	55,424	120,768
Foreign exchange loss	(108,323)	(9,041)
Net loss	(4,362,128)	(4,999,652)
Less: Net loss attributable to the noncontrolling interest in Ocean Power Technologies (Australasia) Pty Ltd.	26,075	4,588
Net loss attributable to Ocean Power Technologies, Inc.	$ (4,336,053)	$ (4,995,064)
Basic and diluted net loss per share (in Dollars per share)	$ (0.42)	$ (0.49)
Weighted average shares used to compute basic and diluted net loss per share (in Shares)	10,295,999	10,268,155

Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
Net loss	$ (4,362,128)	$ (4,999,652)
Foreign currency translation adjustment	(10,484)	(90,079)
Total comprehensive loss	(4,372,612)	(5,089,731)
Comprehensive loss attributable to the noncontrolling interest in Ocean Power Technologies (Australasia) Pty Ltd.	27,136	4,595
Comprehensive loss attributable to Ocean Power Technologies, Inc.	$ (4,345,476)	$ (5,085,136)

- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
Cash flows from operating activities:
Net loss	$ (4,362,128)	$ (4,999,652)
Adjustments to reconcile net loss to net cash used in operating activities:
Foreign exchange loss	108,323	9,041
Depreciation and amortization	116,492	99,140
Loss on disposals of property, plant and equipment		356
Treasury note (discount) premium amortization	7,734	13,914
Compensation expense related to stock option grants and restricted stock	386,550	370,882
Changes in operating assets and liabilities:
Accounts receivable	(99,302)	282,099
Unbilled receivables	(12,443)	(865,244)
Other current assets	120,649	112,335
Other noncurrent assets	(13,252)	(17,994)
Accounts payable	230,884	(397,069)
Accrued expenses	369,247	(373,541)
Unearned revenues	(226,967)	900,540
Net cash used in operating activities	(3,374,213)	(4,865,193)
Cash flows from investing activities:
Purchases of marketable securities	(9,833,736)	(271,005)
Maturities of marketable securities	9,171,233	10,000,000
Restricted cash	75,000
Purchases of equipment	(224,891)	(82,658)
Payments of patent costs		(56,836)
Net cash (used in) provided by investing activities	(812,394)	9,589,501
Cash flows from financing activities:
Repayment of debt	(25,000)	(89,378)
Acquisition of treasury stock	(9,122)	(23,143)
Net cash used in financing activities	(34,122)	(112,521)
Effect of exchange rate changes on cash and cash equivalents	(43,074)	(89,222)
Net (decrease) increase in cash and cash equivalents	(4,263,803)	4,522,565
Cash and cash equivalents, beginning of period	9,353,460	4,376,136
Cash and cash equivalents, end of period	5,089,657	8,898,701
Supplemental disclosure of noncash investing and financing activities:
Capitalized patent costs financed through accounts payable and accrued espenses expenses		24,332
Capitalized purchases of equipment financed through accounts payable and accrued expenses	$ 80,125	$ 19,795

Consolidated Statements of Stockholders’ Equity (Unaudited) - USD ($)	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]	Total
Balance at Apr. 30, 2011	$ 10,419	$ (42,734)	$ 157,174,930	$ (110,848,972)	$ 175,907	$ 21,948	$ 46,491,498
Balance shares (in Shares) at Apr. 30, 2011	10,419,183	(7,685)
Net loss				(4,995,064)		(4,588)	(4,999,652)
Stock based compensation			316,462				316,462
Issuance (forfeiture) of restricted stock, net	$ (8)		54,428				54,420
Issuance (forfeiture) of restricted stock shares, net (in Shares)	(7,888)
Acquisition of treasury stock		$ (23,143)					$ (23,143)
Acquisition of treasury stock shares (in Shares)		(5,800)					5,800
Other comprehensive loss					(90,072)	(7)	$ (90,079)
Balance at Jul. 31, 2011	$ 10,411	$ (65,877)	157,545,820	(115,844,036)	85,835	17,353	41,749,506
Balance shares (in Shares) at Jul. 31, 2011	10,411,295	(13,485)
Balance at Apr. 30, 2012	$ 10,407	$ (102,388)	158,296,458	(125,989,474)	(78,990)	(28,632)	32,107,381
Balance shares (in Shares) at Apr. 30, 2012	10,407,389	(23,544)
Net loss				(4,336,053)		(26,075)	(4,362,128)
Stock based compensation			371,784				371,784
Issuance (forfeiture) of restricted stock, net	$ (2)		14,768				14,766
Issuance (forfeiture) of restricted stock shares, net (in Shares)	(1,950)
Acquisition of treasury stock		$ (9,122)					$ (9,122)
Acquisition of treasury stock shares (in Shares)		(4,274)					4,274
Other comprehensive loss					(9,423)	(1,061)	$ (10,484)
Balance at Jul. 31, 2012	$ 10,405	$ (111,510)	$ 158,683,010	$ (130,325,527)	$ (88,413)	$ (55,768)	$ 28,112,197
Balance shares (in Shares) at Jul. 31, 2012	10,405,439	(27,818)

- Definition

This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

+ Details

- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

+ References + Details

- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Note 1. Background and Basis of Presentation

3 Months Ended

Jul. 31, 2012

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

(1) Background and Basis of Presentation

Ocean Power Technologies, Inc. (the “Company”) was incorporated on April 1984 in New Jersey, commenced business operations in 1994 and re-incorporated in Delaware in April 2007. The Company develops and is seeking to commercialize proprietary systems that generate electricity by harnessing the renewable energy of ocean waves. The Company markets its products in the United States and internationally. Since fiscal 2002, the US Navy and other government agencies have accounted for a significant portion of the Company’s revenues. These revenues were largely for the support of product development efforts. The Company’s goal, over time, is to generate revenues from utilities and other non-government commercial customers, from the sale of products and maintenance services, and to have such revenues represent a greater portion of its total revenues. As we continue to advance our proprietary technologies, we expect to continue to have a net decrease in cash from operating activities unless or until we achieve positive cash flow from the planned commercialization of our products and services.

The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been included. The interim operating results are not necessarily indicative of the results for a full year or for any other interim period. Further information on potential factors that could affect the Company's financial results can be found in the Company's Annual Report on Form 10-K for the year ended April 30, 2012 filed with the Securities and Exchange Commission (“SEC”) and elsewhere in this Form 10-Q.

Consolidation

The accompanying consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Participation of stockholders other than the Company in the net assets and in the earnings or losses of a consolidated subsidiary is reflected as a noncontrolling interest in the Company's Consolidated Balance Sheets and Statements of Operations, which adjusts the Company's consolidated results of operations to reflect only the Company's share of the earnings or losses of the consolidated subsidiary. As of July 31, 2012, there was one noncontrolling interest, consisting of 11.8% of the Company's Australian subsidiary, Ocean Power Technologies (Australasia) Pty. Ltd.

In addition, the Company evaluates its relationships with other entities to identify whether they are variable interest entities, and to assess whether it is the primary beneficiary of such entities. If the determination is made that the Company is the primary beneficiary, then that entity is included in the consolidated financial statements. As of July 31, 2012, there were no such entities.

The Company has a 10% investment in Iberdrola Energias Marinas de Cantabria, S.A. (Iberdrola Cantabria). During the fourth quarter of fiscal 2012, the Company evaluated the realizability of this investment and concluded that it was impaired. The Company recorded an impairment expense of $0.3 million representing 100% of the investment amount. In addition, outstanding receivables from Iberdrola Cantabria in the amount of $0.3 million as of April 2012 were fully reserved during the fourth quarter of fiscal 2012. The investment in Iberdrola Cantabria and net accounts receivable and unbilled receivables from Iberdrola Cantabria were $0 as of July 31, 2012 and April 30, 2012. See Note 9.

Use of Estimates

The preparation of the consolidated financial statements requires management of the Company to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the period. Significant items subject to such estimates and assumptions include the recoverability of the carrying amount of property and equipment and patents; valuation allowances for receivables and deferred income tax assets; and percentage of completion of customer contracts for purposes of revenue recognition. Actual results could differ from those estimates. The current economic environment, particularly the macroeconomic pressures in certain European countries, has increased the degree of uncertainty inherent in those estimates and assumptions.

- Definition

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

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+ Details

Note 2. Summary of Significant Accounting Policies

3 Months Ended

Jul. 31, 2012

Significant Accounting Policies [Text Block]

(2) Summary of Significant Accounting Policies

(a) Revenue Recognition

The Company’s contracts are either cost plus or fixed price contracts. Under cost plus contracts, customers are billed for actual expenses incurred plus an agreed-upon fee. Currently, the Company has two types of fixed price contracts, firm fixed price and cost-sharing. Under firm fixed price contracts, the Company receives an agreed-upon amount for providing products and services specified in the contract. Under cost-sharing contracts, the fixed amount agreed upon with the customer is only intended to fund a portion of the costs on a specific project.

Generally, the Company recognizes revenue using the percentage-of-completion method based on the ratio of costs incurred to total estimated costs at completion. In certain circumstances, revenue under contracts that have specified milestones or other performance criteria may be recognized only when the customer acknowledges that such criteria have been satisfied. In addition, recognition of revenue (and the related costs) may be deferred for fixed-price contracts until contract completion if the Company is unable to reasonably estimate the total costs of the project prior to completion. Because the Company has a small number of contracts, revisions to the percentage-of-completion determination or delays in meeting performance criteria or in completing projects may have a significant effect on revenue for the periods involved. Upon anticipating a loss on a contract, the Company recognizes the full amount of the anticipated loss in the current period.

Under cost plus and firm fixed price contracts there is a profit or loss on the project depending on whether actual costs are more or less than the agreed upon amount. Under cost sharing contracts, an amount corresponding to the revenue is recorded in cost of revenues, resulting in gross profit on these contracts of zero. The Company’s share of the costs is recorded as product development expense.

Unbilled receivables represent expenditures on contracts, plus applicable profit margin, not yet billed. Unbilled receivables are normally billed and collected within one year. Billings made on contracts are recorded as a reduction of unbilled receivables, and to the extent that such billings and cash collections exceed costs incurred plus applicable profit margin, they are recorded as unearned revenues.

(b) Cash and Cash Equivalents

Cash equivalents consist of investments in short-term financial instruments with initial maturities of three months or less from the date of purchase. Cash and cash equivalents include the following:

	July 31, 2012		April 30, 2012

Checking and savings accounts	$	2,545,662		2,051,918
Certificates of deposits and US Treasury obligations		1,404,662		5,998,925
Money market funds		1,139,333		1,302,617
	$	5,089,657		9,353,460

A portion of the Company’s cash is restricted under the terms of two security agreements.

One agreement is between Ocean Power Technologies, Inc. and Barclays Bank. Under this agreement, the cash is on deposit at Barclays Bank and serves as security for letters of credit that are expected to be issued by Barclays Bank on behalf of Ocean Power Technologies Ltd., one of the Company's subsidiaries, under a €800,000 credit facility established by Barclays Bank for Ocean Power Technologies Ltd. The credit facility is for the issuance of letters of credit and bank guarantees and carries a fee of 1% per annum of the amount of any such obligations issued by Barclays Bank. As of July 31, 2012, there were €266,000 in letters of credit outstanding under this agreement. The credit facility does not have an expiration date, but is cancelable at the discretion of the bank.

The other agreement is between Ocean Power Technologies, Inc. and the New Jersey Board of Public Utilities (NJBPU). The Company received a $500,000 recoverable grant award from the NJBPU. Under this agreement, the Company is required to assign to the NJBPU a certificate of deposit in an amount equal to the outstanding grant balance. See Note 6.

Cash restricted under security agreements is as follows:

	July 31, 2012		April 30, 2012

Barclays Bank agreement	$	883,656		953,712
NJBPU agreement		425,000		500,000
	$	1,308,656		1,453,712

(d) Foreign Exchange Gains and Losses

The Company has invested in certain certificates of deposit and has maintained cash accounts that are denominated in British pounds sterling, Euros and Australian dollars. These amounts are included in cash, cash equivalents, restricted cash and marketable securities on the accompanying consolidated balance sheets. Such positions may result in realized and unrealized foreign exchange gains or losses from exchange rate fluctuations, which gains and losses are included in foreign exchange loss in the accompanying consolidated statements of operations.

	Three Months Ended July 31,
	2012			2011

Foreign exchange loss	$	(108,323	)		(9,041	)

	July 31, 2012		April 30, 2012

Foreign currency denominated certificates of deposit and cash accounts	$	2,906,000		2,826,000

(e) Long-Lived Assets

Long-lived assets, such as property and equipment and patents subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of the asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of the asset exceeds its estimated future cash flows, then an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds the fair value of the asset. The Company reviewed its long-lived assets for impairment and determined there was no impairment for the three months ended July 31, 2012.

(f) Concentration of Credit Risk

Financial instruments that potentially subject the Company to concentration of credit risk consist principally of cash balances, bank certificates of deposit and trade receivables. The Company invests its excess cash in highly liquid investments (principally, short-term bank deposits, Treasury bills, Treasury notes and money market funds) and does not believe that it is exposed to any significant risks related to its cash accounts, money market funds or certificates of deposit.

The table below shows the percentage of the Company's revenues derived from customers whose revenues accounted for at least 10% of the Company's consolidated revenues for at least one of the periods indicated:

	Three months ended July 31,
Customer	2012			2011

US Department of Energy		63	%		25	%
European Union (WavePort project)		17	%		—
US Navy		6	%		60	%
UK Government's Technology Strategy Board		5	%		12	%

		91	%		97	%

The loss of, or a significant reduction in revenues from, any of the current customers could significantly impact the Company's financial position or results of operations. The Company does not require its customers to post collateral.

(g) Net Loss per Common Share

Basic and diluted net loss per share for all periods presented is computed by dividing net loss by the weighted average number of shares of common stock outstanding during the period. Due to the Company's net losses, potentially dilutive securities, consisting of outstanding stock options and non-vested performance-based shares, were excluded from the diluted loss per share calculation due to their anti-dilutive effect.

In computing diluted net loss per share, options to purchase shares of common stock and non-vested restricted stock issued to employees and non-employee directors, totaling 1,625,397 for the three months ended July 31, 2012, and 1,560,178 for the three months ended July 31, 2011, were excluded from the computations as the effect would be anti-dilutive due to the Company's losses.

(h) Recently Issued Accounting Standards

During the quarter ended July 31, 2012, the Company adopted the Financial Accounting Standards Board (FASB) amendment to the disclosure requirements for presentation of comprehensive income. The amendment requires that all non-owner changes in stockholders’ equity be presented either in a single continuous statement of comprehensive income or in two separate but consecutive statements. This guidance became effective retrospectively for the interim periods and annual periods beginning after December 15, 2011; however, the FASB agreed to an indefinite deferral of the reclassification requirement. For the Consolidated Statements of Comprehensive Income see page 5.

Note 3. Marketable Securities

3 Months Ended

Jul. 31, 2012

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

(3) Marketable Securities

Marketable securities with initial maturities longer than three months but that mature within one year from the balance sheet date are classified as current assets and are summarized as follows:

	July 31,		April 30,
	2012		2012
Certificates of deposit denominated in Australian dollars	$	356,634		556,437
Certificate of deposit denominated in US dollars		3,360,000		3,806,808
US Treasury obligations		19,300,875		18,006,239

	$	23,017,509		22,369,484

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-Glossary Debt Security
-URI http://asc.fasb.org/extlink&oid=6509901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6511694

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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27405-111563

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 3, 19, 20, 21, 22, 137
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Note 4. Balance Sheet Detail

3 Months Ended

Jul. 31, 2012

Supplemental Balance Sheet Disclosures [Text Block]

(4) Balance Sheet Detail

	July 31, 2012			April 30, 2012

Accounts Receivable, net
Accounts receivable	$	1,452,053			1,369,400
Allowance for doubtful accounts		(294,262	)		(304,604	)
	$	1,157,791			1,064,796

Property and Equipment
Property and Equipment	$	2,459,440			2,213,820
Accumulated depreciation and amortization		(1,579,422	)		(1,530,887	)
	$	880,018			682,933

Patents
Patents	$	1,574,044			1,574,044
Accumulated amortization		(358,796	)		(304,587	)
	$	1,215,248			1,269,457


Accrued Expenses
Project costs	$	1,025,521			244,892
Contract loss reserves		785,000			785,000
Employee incentive payments		165,083			661,328
Other		224,277			185,320
Employee-related costs		439,840			354,966
Payroll tax withholdings		156,626			166,092
Investment in joint venture		163,216			176,110
Legal and accounting fees		209,678			193,720
Value-added tax		7,590			2,666
	$	3,176,831			2,770,094

Note 5. Related Party Transactions

3 Months Ended

Jul. 31, 2012

(5) Related Party Transactions

In August 1999, the Company entered into a consulting agreement with an individual for the provision of marketing services. Currently, this agreement provides for fees at a rate of $950 per day of services provided. The individual became a member of the board of directors in June 2006. In addition, this individual is also the chief executive officer of a company that provides engineering and technical services to the Company. The Company also provides services to the company where this individual is the chief executive officer.

	Three Months Ended July 31,
	2012		2011
Related party consulting expense	$	21,000		21,000
Expenses for services provided by related party company		-		22,000
Revenue for services provided to related party company		17,000		16,000

	July 31, 2012		April 30, 2012

Consulting fees payable to related party	$	7,000		7,000
Payable to related party company		-		-
Receivable from related party company		13,000		-

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph b
-Article 3A

Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 1-4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Note 6. Debt

3 Months Ended

Jul. 31, 2012

Debt Disclosure [Text Block]

(6) Debt

The Company was awarded a recoverable grant totaling $500,000 from the NJBPU under the Renewable Energy Business Venture Assistance Program. Under the terms of this agreement, the amount to be repaid is a fixed monthly amount of principal only, repayable over a five-year period beginning in November 2011. As of both July 31, 2012 and April 30, 2012, $100,000 was included in the current portion of long-term debt on the accompanying consolidated balance sheets. The terms also required the Company to assign to the NJBPU a certificate of deposit in an amount equal to the outstanding grant balance. See Note 2(c).

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References + Details

Note 7. Deferred Credits Payable and Deferred Credits

3 Months Ended

Jul. 31, 2012

Customer Advances And Deposits Disclosure [Text Block]

(7) Deferred Credits Payable and Deferred Credits

During the year ended April 30, 2001, in connection with the sale of common stock to an investor, the Company received $600,000 from the investor in exchange for an option to purchase up to 500,000 metric tons of carbon emissions credits generated by the Company during the years 2008 through 2012, at a 30% discount from the then-prevailing market rate. This amount has been recorded as deferred credits payable in the accompanying consolidated balance sheets as of July 31, 2012 and April 30, 2012, respectively. If the Company does not become entitled under applicable laws to the full amount of emission credits covered by the option by December 31, 2012, the Company is obligated to return the option fee of $600,000, less the aggregate discount on any emission credits sold to the investor prior to such date. If the Company receives emission credits under applicable laws and fails to sell to the investor the credits up to the full amount of emission credits covered by the option, the investor is entitled to liquidated damages equal to 30% of the aggregate market value of the shortfall in emission credits (subject to a limit on the market price of emission credits). As of July 31, 2012, the Company has not generated any emissions credits eligible for purchase under the agreement and the Company does not expect to generate any eligible emissions credits before December 31, 2012. Accordingly, this amount has been classified as a current liability as of July 31, 2012 and April 30, 2012.

Note 8. Stock-Based Compensation

3 Months Ended

Jul. 31, 2012

Disclosure of Compensation Related Costs, Share-based Payments [Text Block]

(8) Stock-Based Compensation

Costs resulting from all stock-based payment transactions are recognized in the consolidated financial statements at their fair values. Compensation cost for the portion of the awards for which the requisite service had not been rendered that were outstanding as of May 1, 2006 is being recognized in the consolidated statements of operations over the remaining service period after such date based on the award's original estimated fair value. The aggregate stock-based compensation expense related to all stock-based transactions recorded in the consolidated statements of operations was approximately $387,000 and $371,000 for the three months ended July 31, 2012 and 2011, respectively.

(a) Stock Options

Valuation Assumptions for Options Granted During the Three Months Ended July 31, 2012 and 2011

The fair value of each stock option granted, for both service-based and performance-based vesting requirements, during the three months ended July 31, 2012 and 2011 was estimated at the date of grant using the Black-Scholes option pricing model, assuming no dividends and using the weighted average valuation assumptions noted in the following table. The risk-free rate is based on the US Treasury yield curve in effect at the time of grant. The expected life (estimated period of time outstanding) of the stock options granted was estimated using the "simplified" method as permitted by the SEC's Staff Accounting Bulletin No. 107, Share-Based Payment. Expected volatility was based on historical volatility for a peer group of companies for a period equal to the stock option's expected life, calculated on a daily basis.

	Three Months Ended July 31,
	2012			2011
Risk-free interest rate		0.9	%		2.1	%
Expected dividend yield		0.0	%		0.0	%
Expected life	6.3 years			6.3 years
Expected volatility		86.15	%		94	%

The above assumptions were used to determine the weighted average per share fair value of $1.46 and $3.15 for stock options granted during the three months ended July 31, 2012 and 2011, respectively.

A summary of stock options under the plans is as follows:

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2012		1,353,473		$	8.92
Forfeited		(38,813	)		6.85
Exercised		—			—
Granted		233,896			1.79
Outstanding as of July 31, 2012		1,548,556			7.89		6.4
Exercisable as of July 31, 2012		930,251			10.50		4.8

The total intrinsic value of outstanding and exercisable options as of July 31, 2012 was approximately $144,000. As of July 31, 2012, approximately 618,000 additional options are expected to vest in the future, which options had approximately $144,000 of intrinsic value and a weighted average remaining contractual term of 8.7 years. There was approximately $372,000 and $316,000 of total recognized compensation cost related to stock options for the three months ended July 31, 2012 and 2011, respectively. As of July 31, 2012, there was approximately $1,461,000 of total unrecognized compensation cost related to non-vested stock options granted under the plans. This cost is expected to be recognized over a weighted-average period of 3.0 years. The Company normally issues new shares to satisfy option exercises under these plans. During the three months ended July 31, 2012, stock options granted included 25,128 stock options which are subject to performance-based vesting requirements. Stock options outstanding as of July 31, 2012 included 38,894 stock options subject to performance-based vesting requirements.

(b) Restricted Stock

Compensation expense for non-vested restricted stock was historically recorded based on its market value on the date of grant and recognized over the associated service and performance period. During the three months ended July 31, 2012, there were 18,000 shares of non-vested restricted stock granted to employees with performance-based vesting requirements. During the three months ended July 31, 2012, 19,950 shares of non-vested restricted stock subject to performance-based vesting requirements were forfeited in accordance with performance objectives. Restricted stock issued and unvested at July 31, 2012 included 52,000 shares of non-vested restricted stock subject to performance-based vesting requirements.

A summary of non-vested restricted stock under the plans is as follows:

	Number of Shares			Weighted Average Price per Share

Issued and unvested at April 30, 2012		93,840		$	5.86
Granted		18,000			2.00
Forfeited		(19,950	)		5.97
Vested		(15,049	)		5.97
Issued and unvested at July 31, 2012		76,841			4.91

There was approximately $15,000 and $54,000 of total recognized compensation cost related to restricted stock for the three months ended July 31, 2012 and 2011, respectively. As of July 31, 2012, there was approximately $65,000 of total unrecognized compensation cost related to non-vested restricted stock granted under the plans. This cost is expected to be recognized over a weighted average period of 2.8 years.

(c)Treasury Stock

During the three months ended July 31, 2012 and 2011, 4,274 and 5,800 shares, respectively, of common stock were purchased by the Company from employees to pay taxes related to the vesting of restricted stock.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 50
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6406099&loc=d3e25284-112666

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64, 65, A240
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 93-6
-Paragraph 53
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Note 9. Commitments and Contingencies

3 Months Ended

Jul. 31, 2012

Commitments and Contingencies Disclosure [Text Block]

(9) Commitments and Contingencies

Litigation

The Company is involved from time to time in certain legal actions arising in the ordinary course of business. Management believes that the outcome of such actions will not have a material adverse effect on the Company's financial position or results of operations.

Spain Construction Agreement

The Company is currently engaged with Iberdrola Cantabria in discussions regarding modifications to its agreement for the first phase of the construction of a wave power project off the coast of Spain. This first phase was due to be completed by December 31, 2009. If no modification is agreed to by the parties, the customer may, subject to certain conditions in the agreement, terminate the agreement and would not be obligated to make any more milestone payments. The agreement also provides that the customer may seek reimbursement for direct damages only, limited to amounts specified in the agreement, if the Company is in default of its obligations under the agreement. As of July 31, 2012, the Company does not believe that the outcome of this matter will have a material adverse effect on the Company's financial position or results of operations. See Note 1.

- Definition

The entire disclosure for commitments and contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Number 14
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Note 10. Income Taxes

3 Months Ended

Jul. 31, 2012

Income Tax Disclosure [Text Block]

(10) Income Taxes

The Company did not recognize any consolidated income tax benefit (expense) for the three month periods ended July 31, 2012 and 2011. The Company has recorded a valuation allowance to reduce its net deferred tax asset to an amount that is more likely than not to be realized in future years. Accordingly, the benefit of the net operating loss that would have been recognized was offset by changes in the valuation allowance.

During the three months ended July 31, 2012, the Company had no material changes in uncertain tax positions.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
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-Number 109
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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-Article 4

Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Note 11. Operating Segments and Geographic Information

3 Months Ended

Jul. 31, 2012

Segment Reporting Disclosure [Text Block]

(11) Operating Segments and Geographic Information

The Company views its business as one segment, which is the development and sale of its PowerBuoy product for wave energy applications. The Company operates on a worldwide basis with one operating company in the US, one operating subsidiary in the UK and one operating subsidiary in Australia, which are categorized below as North America, Europe, and Asia and Australia, respectively. Revenues are generally attributed to the operating unit that bills the customers.

Geographic information is as follows:

	North America			Europe			Asia and Australia			Total
Three months ended July 31, 2012
Revenues from external customers	$	930,903			51,493			—			982,396
Operating loss		(3,851,720	)		(234,974	)		(222,535	)		(4,309,229	)

Three months ended July 31, 2011
Revenues from external customers		1,688,551			222,301			—			1,910,852
Operating loss		(4,647,691	)		(413,622	)		(50,066	)		(5,111,379	)

July 31, 2012
Long-lived assets		791,939			88,079			—			880,018
Total assets		32,010,213			1,295,258			511,789			33,817,260

April 30, 2012
Long-lived assets		585,818			97,115			—			682,933
Total assets	$	35,181,637			1,619,973			640,027			37,441,637

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Accounting Policies, by Policy (Policies)	3 Months Ended
Accounting Policies, by Policy (Policies)	Jul. 31, 2012
Basis of Accounting, Policy [Policy Text Block]	Background and Basis of Presentation Ocean Power Technologies, Inc. (the "Company") was incorporated on April 1984 in New Jersey, commenced business operations in 1994 and re-incorporated in Delaware in April2007. The Company develops and is seeking to commercialize proprietary systems that generate electricity by harnessing the renewable energy of ocean waves. The Company markets its products in the United States and internationally. Since fiscal 2002, the US Navy and other government agencies have accounted for a significant portion of the Company's revenues.These revenues were largely for the support of product development efforts. The Company's goal, over time, is to generate revenues from utilities and other non-government commercial customers, from the sale of products and maintenance services, and to have such revenues represent a greater portion of its total revenues. As we continue to advance our proprietary technologies, we expect to continue to have a net decrease in cash from operating activities unless or until we achieve positive cash flow from the planned commercialization of our products and services. The accompanying unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article10 of RegulationS-X. Accordingly, they do not include all the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been included. The interim operating results are not necessarily indicative of the results for a full year or for any other interim period. Further information on potential factors that could affect the Company's financial results can be found in the Company's Annual Report on Form10-K for the year ended April30, 2012 filed with the Securities and Exchange Commission ("SEC")and elsewhere in this Form 10-Q.
Consolidation, Policy [Policy Text Block]	Consolidation The accompanying consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Participation of stockholders other than the Company in the net assets and in the earnings or losses of a consolidated subsidiary is reflected as a noncontrolling interest in the Company's Consolidated Balance Sheets and Statements of Operations, which adjusts the Company's consolidated results of operations to reflect only the Company's share of the earnings or losses of the consolidated subsidiary. As of July 31, 2012, there was one noncontrolling interest, consisting of 11.8% of the Company's Australian subsidiary, Ocean Power Technologies (Australasia) Pty. Ltd. In addition, the Company evaluates its relationships with other entities to identify whether they are variable interest entities, and to assess whether it is the primary beneficiary of such entities. If the determination is made that the Company is the primary beneficiary, then that entity is included in the consolidated financial statements. As of July 31, 2012, there were no such entities. The Company has a 10% investment in Iberdrola Energias Marinas de Cantabria, S.A. (Iberdrola Cantabria). During the fourth quarter of fiscal 2012, the Company evaluated the realizability of this investment and concluded that it was impaired. The Company recorded an impairment expense of $0.3 million representing 100% of the investment amount. In addition, outstanding receivables from Iberdrola Cantabria in the amount of $0.3 million as of April 2012 were fully reserved during the fourth quarter of fiscal 2012. The investment in Iberdrola Cantabria and net accounts receivable and unbilled receivables from Iberdrola Cantabria were $0 as of July 31, 2012 and April30, 2012. See Note9.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of the consolidated financial statements requires management of the Company to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the period. Significant items subject to such estimates and assumptions include the recoverability of the carrying amount of property and equipment and patents; valuation allowances for receivables and deferred income tax assets; and percentage of completion of customer contracts for purposes of revenue recognition. Actual results could differ from those estimates. The current economic environment, particularly the macroeconomic pressures in certain European countries, has increased the degree of uncertainty inherent in those estimates and assumptions.
Revenue Recognition, Policy [Policy Text Block]	(a)Revenue Recognition The Company's contracts are either cost plus or fixed price contracts. Under cost plus contracts, customers are billed for actual expenses incurred plus an agreed-upon fee. Currently, the Company has two types of fixed price contracts, firm fixed price and cost-sharing. Under firm fixed price contracts, the Company receives an agreed-upon amount for providing products and services specified in the contract. Under cost-sharing contracts, the fixed amount agreed upon with the customer is only intended to fund a portion of the costs on a specific project. Generally, the Company recognizes revenue using the percentage-of-completion method based on the ratio of costs incurred to total estimated costs at completion. In certain circumstances, revenue under contracts that have specified milestones or other performance criteria may be recognized only when the customer acknowledges that such criteria have been satisfied. In addition, recognition of revenue (and the related costs) may be deferred for fixed-price contracts until contract completion if the Company is unable to reasonably estimate the total costs of the project prior to completion. Because the Company has a small number of contracts, revisions to the percentage-of-completion determination or delays in meeting performance criteria or in completing projects may have a significant effect on revenue for the periods involved. Upon anticipating a loss on a contract, the Company recognizes the full amount of the anticipated loss in the current period. Under cost plus and firm fixed price contracts there is a profit or loss on the project depending on whether actual costs are more or less than the agreed upon amount. Under cost sharing contracts, an amount corresponding to the revenue is recorded in cost of revenues, resulting in gross profit on these contracts of zero. The Company's share of the costs is recorded as product development expense. Unbilled receivables represent expenditures on contracts, plus applicable profit margin, not yet billed. Unbilled receivables are normally billed and collected within one year. Billings made on contracts are recorded as a reduction of unbilled receivables, and to the extent that such billings and cash collections exceed costs incurred plus applicable profit margin, they are recorded as unearned revenues.
Cash and Cash Equivalents, Policy [Policy Text Block]	(b)Cash and Cash Equivalents Cash equivalents consist of investments in short-term financial instruments with initial maturities of three months or less from the date of purchase.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]	(c)Restricted Cash and Credit Facility A portion of the Company's cash is restricted under the terms of two security agreements. One agreement is between Ocean Power Technologies, Inc. and Barclays Bank. Under this agreement, the cash is on deposit at Barclays Bank and serves as security for letters of credit that are expected to be issued by Barclays Bank on behalf of Ocean Power Technologies Ltd., one of the Company's subsidiaries, under a 800,000 credit facility established by Barclays Bank for Ocean Power Technologies Ltd. The credit facility is for the issuance of letters of credit and bank guarantees and carries a fee of 1% per annum of the amount of any such obligations issued by Barclays Bank. As of July 31, 2012, there were 266,000 in letters of credit outstanding under this agreement. The credit facility does not have an expiration date, but is cancelable at the discretion of the bank. The other agreement is between Ocean Power Technologies, Inc. and the New Jersey Board of Public Utilities (NJBPU). The Company received a $500,000 recoverable grant award from the NJBPU. Under this agreement, the Company is required to assign to the NJBPU a certificate of deposit in an amount equal to the outstanding grant balance. See Note 6.
Foreign Currency Transactions and Translations Policy [Policy Text Block]	(d)Foreign Exchange Gains and Losses The Company has invested in certain certificates of deposit and has maintained cash accounts that are denominated in British pounds sterling, Euros and Australian dollars. These amounts are included in cash, cash equivalents, restricted cash and marketable securities on the accompanying consolidated balance sheets. Such positions may result in realized and unrealized foreign exchange gains or losses from exchange rate fluctuations, which gains and losses are included in foreign exchange lossin the accompanying consolidated statements of operations.
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	(e)Long-Lived Assets Long-lived assets, such as property and equipment and patents subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of the asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of the asset exceeds its estimated future cash flows, then an impairment charge is recognized in the amount by which the carrying amount of the asset exceeds the fair value of the asset. The Company reviewed its long-lived assets for impairment and determined there was no impairment for the three months ended July 31, 2012.
Concentration Risk, Credit Risk, Policy [Policy Text Block]	(f)Concentration of Credit Risk Financial instruments that potentially subject the Company to concentration of credit risk consist principally of cash balances, bank certificates of deposit and trade receivables. The Company invests its excess cash in highly liquid investments (principally, short-term bank deposits, Treasury bills, Treasury notes and money market funds) and does not believe that it is exposed to any significant risks related to its cash accounts, money market funds or certificates of deposit. The table below shows the percentage of the Company's revenues derived from customers whose revenues accounted for at least 10% of the Company's consolidated revenues for at least one of the periods indicated: Three months ended July 31, Customer 2012 2011 US Department of Energy 63 % 25 % European Union (WavePort project) 17 % - US Navy 6 % 60 % UK Government's Technology Strategy Board 5 % 12 % 91 % 97 % The loss of, or a significant reduction in revenues from, any of the current customers could significantly impact the Company's financial position or results of operations. The Company does not require its customers to post collateral.
Earnings Per Share, Policy [Policy Text Block]	(g)Net Loss per Common Share Basic and diluted net loss per share for all periods presented is computed by dividing net loss by the weighted average number of shares of common stock outstanding during the period. Due to the Company's net losses, potentially dilutive securities, consisting of outstanding stock options and non-vested performance-based shares, were excluded from the diluted loss per share calculation due to their anti-dilutive effect. In computing diluted net loss per share, options to purchase shares of common stock and non-vested restricted stock issued to employees and non-employee directors, totaling 1,625,397 for the three months ended July 31, 2012, and 1,560,178 for the three months ended July 31, 2011, were excluded from the computations as the effect would be anti-dilutive due to the Company's losses.
New Accounting Pronouncements, Policy [Policy Text Block]	(h) Recently Issued Accounting Standards During the quarter ended July 31, 2012, the Company adopted the Financial Accounting Standards Board (FASB) amendment to the disclosure requirements for presentation of comprehensive income. The amendment requires that all non-owner changes in stockholders' equity be presented either in a single continuous statement of comprehensive income or in two separate but consecutive statements. This guidance became effective retrospectively for the interim periods and annual periods beginning after December15, 2011; however, the FASB agreed to an indefinite deferral of the reclassification requirement. For the Consolidated Statements of Comprehensive Income see page 5.

Note 2. Summary of Significant Accounting Policies (Tables)

3 Months Ended

Jul. 31, 2012

Schedule of Cash and Cash Equivalents [Table Text Block]

	July 31, 2012		April 30, 2012

Checking and savings accounts	$	2,545,662		2,051,918
Certificates of deposits and US Treasury obligations		1,404,662		5,998,925
Money market funds		1,139,333		1,302,617
	$	5,089,657		9,353,460

Schedule of Restricted Cash and Cash Equivalents [Table Text Block]

	July 31, 2012		April 30, 2012

Barclays Bank agreement	$	883,656		953,712
NJBPU agreement		425,000		500,000
	$	1,308,656		1,453,712

Schedule of Cash and Cash Equivalents, Restricted Cash and Marketable Securities [Table Text Block]

	Three Months Ended July 31,
	2012			2011

Foreign exchange loss	$	(108,323	)		(9,041	)

	July 31, 2012		April 30, 2012

Foreign currency denominated certificates of deposit and cash accounts	$	2,906,000		2,826,000

Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]

	Three months ended July 31,
Customer	2012			2011

US Department of Energy		63	%		25	%
European Union (WavePort project)		17	%		—
US Navy		6	%		60	%
UK Government's Technology Strategy Board		5	%		12	%

		91	%		97	%

Note 3. Marketable Securities (Tables)

3 Months Ended

Jul. 31, 2012

Marketable Securities [Table Text Block]

	July 31,		April 30,
	2012		2012
Certificates of deposit denominated in Australian dollars	$	356,634		556,437
Certificate of deposit denominated in US dollars		3,360,000		3,806,808
US Treasury obligations		19,300,875		18,006,239

	$	23,017,509		22,369,484

Note 4. Balance Sheet Detail (Tables)

3 Months Ended

Jul. 31, 2012

Schedule of Other Assets and Other Liabilities [Table Text Block]

	July 31, 2012			April 30, 2012

Accounts Receivable, net
Accounts receivable	$	1,452,053			1,369,400
Allowance for doubtful accounts		(294,262	)		(304,604	)
	$	1,157,791			1,064,796

Property and Equipment
Property and Equipment	$	2,459,440			2,213,820
Accumulated depreciation and amortization		(1,579,422	)		(1,530,887	)
	$	880,018			682,933

Patents
Patents	$	1,574,044			1,574,044
Accumulated amortization		(358,796	)		(304,587	)
	$	1,215,248			1,269,457


Accrued Expenses
Project costs	$	1,025,521			244,892
Contract loss reserves		785,000			785,000
Employee incentive payments		165,083			661,328
Other		224,277			185,320
Employee-related costs		439,840			354,966
Payroll tax withholdings		156,626			166,092
Investment in joint venture		163,216			176,110
Legal and accounting fees		209,678			193,720
Value-added tax		7,590			2,666
	$	3,176,831			2,770,094

Note 5. Related Party Transactions (Tables)

3 Months Ended

Jul. 31, 2012

Director [Member]

	July 31, 2012		April 30, 2012

Consulting fees payable to related party	$	7,000		7,000
Payable to related party company		-		-
Receivable from related party company		13,000		-

	Three Months Ended July 31,
	2012		2011
Related party consulting expense	$	21,000		21,000
Expenses for services provided by related party company		-		22,000
Revenue for services provided to related party company		17,000		16,000

Note 8. Stock-Based Compensation (Tables)

3 Months Ended

Jul. 31, 2012

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Three Months Ended July 31,
	2012			2011
Risk-free interest rate		0.9	%		2.1	%
Expected dividend yield		0.0	%		0.0	%
Expected life	6.3 years			6.3 years
Expected volatility		86.15	%		94	%

Schedule of Share-based Compensation, Activity [Table Text Block]

	Shares Underlying Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
Outstanding as of April 30, 2012		1,353,473		$	8.92
Forfeited		(38,813	)		6.85
Exercised		—			—
Granted		233,896			1.79
Outstanding as of July 31, 2012		1,548,556			7.89		6.4
Exercisable as of July 31, 2012		930,251			10.50		4.8

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

	Number of Shares			Weighted Average Price per Share

Issued and unvested at April 30, 2012		93,840		$	5.86
Granted		18,000			2.00
Forfeited		(19,950	)		5.97
Vested		(15,049	)		5.97
Issued and unvested at July 31, 2012		76,841			4.91

Note 11. Operating Segments and Geographic Information (Tables)

3 Months Ended

Jul. 31, 2012

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]

	North America			Europe			Asia and Australia			Total
Three months ended July 31, 2012
Revenues from external customers	$	930,903			51,493			—			982,396
Operating loss		(3,851,720	)		(234,974	)		(222,535	)		(4,309,229	)

Three months ended July 31, 2011
Revenues from external customers		1,688,551			222,301			—			1,910,852
Operating loss		(4,647,691	)		(413,622	)		(50,066	)		(5,111,379	)

July 31, 2012
Long-lived assets		791,939			88,079			—			880,018
Total assets		32,010,213			1,295,258			511,789			33,817,260

April 30, 2012
Long-lived assets		585,818			97,115			—			682,933
Total assets	$	35,181,637			1,619,973			640,027			37,441,637

Note 1. Background and Basis of Presentation (Detail) - USD ($)	3 Months Ended
	Apr. 30, 2012	Jul. 31, 2012
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		11.80%
Noncontrolling Interest, Ownership Percentage by Parent		10.00%
Asset Impairment Charges	$ 300,000
Asset Impairment Charge As Percent Of Investment Amount	100.00%
Accounts Receivable, Gross	$ 0.3
Accounts Receivable, Net	$ 0	$ 0

Note 2. Summary of Significant Accounting Policies (Detail)	3 Months Ended
	Jul. 31, 2012 USD ($) shares	Jul. 31, 2011 shares	Jul. 31, 2012 EUR (€)	Nov. 30, 2011 USD ($)
New Jersey Board of Public Utilities [Member]
Long-term Debt (in Dollars)	$ 500,000
Contract Gross Profit (in Dollars)	$ 0
Line of Credit Facility, Current Borrowing Capacity (in Euro) \| €			€ 800,000
Line of Credit Facility, Interest Rate at Period End	1.00%		1.00%
Line of Credit Facility, Amount Outstanding (in Euro) \| €			€ 266,000
Long-term Debt (in Dollars)				$ 500,000
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares) \| shares	1,625,397	1,560,178

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

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-URI http://asc.fasb.org/extlink&oid=6510752

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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 40
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 07-4
-Paragraph 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 171
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Note 2. Summary of Significant Accounting Policies (Detail) - Cash and Cash Equivalents - USD ($)	Jul. 31, 2012	Apr. 30, 2012	Jul. 31, 2011	Apr. 30, 2011
Checking and savings accounts [Member]
Cash and cash equivalents	$ 2,545,662	$ 2,051,918
Certificates of deposits and US Treasury obligations [Member]
Cash and cash equivalents	1,404,662	5,998,925
Money Market Funds [Member]
Cash and cash equivalents	1,139,333	1,302,617
Cash and cash equivalents	$ 5,089,657	$ 9,353,460	$ 8,898,701	$ 4,376,136

- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6676-107765

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3044-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 1
-Article 5

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7, 26
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7
-Footnote 1
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 8, 9
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Note 2. Summary of Significant Accounting Policies (Detail) - Cash Restricted Under Security Agreements - USD ($)	Jul. 31, 2012	Apr. 30, 2012
Barclays Bank [Member]
Cash restricted under security agreements	$ 883,656	$ 953,712
NJBPU [Member]
Cash restricted under security agreements	425,000	500,000
Cash restricted under security agreements	$ 1,308,656	$ 1,453,712

Note 2. Summary of Significant Accounting Policies (Detail) - Foreign Exchange Gain (Loss) - USD ($)	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
Foreign exchange loss	$ (108,323)	$ (9,041)

- Definition

The aggregate foreign currency transaction gain (loss) (both realized and unrealized) included in determining net income for the reporting period. Excludes foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements. For certain enterprises, primarily banks, that are dealers in foreign exchange, foreign currency transaction gains (losses) may be disclosed as dealer gains (losses).

+ References + Details

Note 2. Summary of Significant Accounting Policies (Detail) - Foreign Currency Denominated Certificates of Deposit and Cash Accounts - USD ($)	Jul. 31, 2012	Apr. 30, 2012
Foreign currency denominated certificates of deposit and cash accounts	$ 2,906,000	$ 2,826,000

Note 2. Summary of Significant Accounting Policies (Detail) - Percentage of the Company’s Revenues Derived From Customers	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
US Department of Energy [Member]
Customer	63.00%	25.00%
European Union [Member]
Customer	17.00%
US Navy [Member]
Customer	6.00%	60.00%
UK Government's Technology Strategy Board [Member]
Customer	5.00%	12.00%
Customer	91.00%	97.00%

Note 3. Marketable Securities (Detail) - Marketable Securities That Mature Within One Year - USD ($)	Jul. 31, 2012	Apr. 30, 2012
Certificates of deposit denominated in Australian dollars [Member]
Marketable Securities	$ 356,634	$ 556,437
Certificate of deposit denominated in US dollars [Member]
Marketable Securities	3,360,000	3,806,808
US Treasury obligations [Member]
Marketable Securities	19,300,875	18,006,239
Marketable Securities	$ 23,017,509	$ 22,369,484

Note 4. Balance Sheet Detail (Detail) - Balance Sheet Detail - USD ($)	Jul. 31, 2012	Apr. 30, 2012
Investment in Joint Venture [Member]
Accrued Expenses
Other Accrued Liabilities, Current	$ 163,216	$ 176,110
Other Accrued [Member]
Accrued Expenses
Other Accrued Liabilities, Current	224,277	185,320
Accounts receivable	1,452,053	1,369,400
Allowance for doubtful accounts	(294,262)	(304,604)
	1,157,791	1,064,796
Property and Equipment	2,459,440	2,213,820
Accumulated depreciation and amortization	(1,579,422)	(1,530,887)
	880,018	682,933
Patents	1,574,044	1,574,044
Accumulated amortization	(358,796)	(304,587)
	1,215,248	1,269,457
Project costs	1,025,521	244,892
Contract loss reserves	785,000	785,000
Employee incentive payments	165,083	661,328
Legal and accounting fees	209,678	193,720
Value-added tax	7,590	2,666
Employee-related costs	439,840	354,966
Payroll tax withholdings	156,626	166,092
	$ 3,176,831	$ 2,770,094

Note 5. Related Party Transactions (Detail)	Jul. 31, 2012 USD ($)
Related Party Daily Transaction Rate	$ 950

Note 5. Related Party Transactions (Detail) - Related Party Transactions - USD ($)	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
Related party consulting expense	$ 21,000	$ 21,000
Expenses for services provided by related party company		22,000
Revenue for services provided to related party company	$ 17,000	$ 16,000

Note 5. Related Party Transactions (Detail) - Additional Related Party Transactions - USD ($)	Jul. 31, 2012	Apr. 30, 2012
Consulting fees payable to related party	$ 7,000	$ 7,000
Receivable from related party company	$ 13,000

- Definition

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

+ References + Details

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References + Details

Note 6. Debt (Detail) - USD ($)	Jul. 31, 2012	Apr. 30, 2012	Nov. 30, 2011
Long-term Debt			$ 500,000
Long Term Debt Payment Terms			5 years
Long-term Debt, Current Maturities	$ 100,000	$ 100,000

Note 7. Deferred Credits Payable and Deferred Credits (Detail)	Jul. 31, 2012 USD ($)	Apr. 30, 2012 USD ($)	Apr. 30, 2001 USD ($) T
Customer Advances and Deposits (in Dollars)			$ 600,000
Deferred Credits Payable Option Details (in US Ton) \| T			500,000
Deferred Credits Payable Market Discount Rate			30.00%
Customer Advances and Deposits, Current (in Dollars)	$ 600,000	$ 600,000
Deferred Credits Payable Market Liquidated Damages Rate	30.00%

Note 8. Stock-Based Compensation (Detail) - USD ($)	3 Months Ended
Note 8. Stock-Based Compensation (Detail) - USD ($)	Jul. 31, 2012	Jul. 31, 2011
Stock Options [Member]
Share-based Compensation	$ 372,000	$ 316,000
Performance-based vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number (in Shares)	38,894
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	25,128
Restricted Stock [Member]
Allocated Share-based Compensation Expense	$ 15,000	54,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	2 years 292 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)	18,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures (in Shares)	19,950
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in Shares)	52,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 65,000
Allocated Share-based Compensation Expense	$ 387,000	$ 371,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)	$ 1.46	$ 3.15
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 144,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number (in Shares)	618,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value	$ 144,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term	8 years 255 days
Share-based Compensation	$ 386,550	$ 370,882
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options	$ 1,461,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	233,896
Treasury Stock, Shares, Acquired (in Shares)	4,274	5,800

Note 8. Stock-Based Compensation (Detail) - Weighted Average Fair Value Assumptions for Stock-Based Compensation	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
Risk-free interest rate	0.90%	2.10%
Expected dividend yield	0.00%	0.00%
Expected life	6 years 109 days	6 years 109 days
Expected volatility	86.15%	94.00%

Note 8. Stock-Based Compensation (Detail) - Stock Options Under the Plans	3 Months Ended
	Jul. 31, 2012 $ / shares shares
Shares Underlying Options \| shares	1,353,473
Weighted Average Exercise Price (in Dollars per share) \| $ / shares	$ 8.92
Weighted Average Remaining Contractual Term (In Years)	6 years 146 days
Exercisable as of July 31, 2012 \| shares	930,251
Exercisable as of July 31, 2012 (in Dollars per share) \| $ / shares	$ 10.50
Exercisable as of July 31, 2012	4 years 292 days
Forfeited \| shares	(38,813)
Forfeited (in Dollars per share) \| $ / shares	$ 6.85
Granted \| shares	233,896
Granted (in Dollars per share) \| $ / shares	$ 1.79
Shares Underlying Options \| shares	1,548,556
Weighted Average Exercise Price (in Dollars per share) \| $ / shares	$ 7.89

Note 8. Stock-Based Compensation (Detail) - Non-Vested Restricted Stock Under the Plans - Unvested [Member]	3 Months Ended
	Jul. 31, 2012 $ / shares shares
Number of Shares \| shares	93,840
Weighted Average Price Per Share (in Dollars per share) \| $ / shares	$ 5.86
Granted \| shares	18,000
Granted (in Dollars per share) \| $ / shares	$ 2.00
Forfeited \| shares	(19,950)
Forfeited (in Dollars per share) \| $ / shares	$ 5.97
Vested \| shares	(15,049)
Vested (in Dollars per share) \| $ / shares	$ 5.97
Number of Shares \| shares	76,841
Weighted Average Price Per Share (in Dollars per share) \| $ / shares	$ 4.91

- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References + Details

Note 11. Operating Segments and Geographic Information (Detail)	3 Months Ended
	Jan. 31, 2012
United States [Member]
Number of Reportable Segments	1
United Kingdom [Member]
Number of Reportable Segments	1
Australia [Member]
Number of Reportable Segments	1
Number of Operating Segments	1

Note 11. Operating Segments and Geographic Information (Detail) - Geographic Segment Information - USD ($)	3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Apr. 30, 2012
North America [Member]
Revenues from external customers	$ 930,903	$ 1,688,551
Operating loss	(3,851,720)	(4,647,691)
July 31, 2012
Long-lived assets	791,939		$ 585,818
Total assets	32,010,213		35,181,637
Europe [Member]
Revenues from external customers	51,493	222,301
Operating loss	(234,974)	(413,622)
July 31, 2012
Long-lived assets	88,079		97,115
Total assets	1,295,258		1,619,973
Asia and Australia [Member]
Operating loss	(222,535)	(50,066)
July 31, 2012
Total assets	511,789		640,027
Revenues from external customers	982,396	1,910,852
Operating loss	(4,309,229)	$ (5,111,379)
Long-lived assets	880,018		682,933
Total assets	$ 33,817,260		$ 37,441,637