STOCK OPTION PLANS (Details 1) (USD $)	12 Months Ended
Apr. 30, 2013	Apr. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number ofShares, Outstanding	33,819
Number ofShares, Granted	97,143
Number ofShares, Outstanding	116,279	33,819
Number of Shares, Exercisable, April 30, 2013	107,516	29,262
Weighted-average, Exercise Price, Outstanding	$ 28.42
Weighted-average, Exercise Price, Outstanding	$ 6.70	$ 28.42
Weighted-average, Exercise Price, Exercisable, April 30, 2013	$ 6.92	$ 29.45
Weighted- average Remaining Contractual Term, Outstanding, April 30, 2013	3 years 10 months 17 days	1 year 8 months 1 day
2002 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number ofShares, Outstanding	5,991
Number ofShares, Granted	12,857
Number ofShares, Exercised	0
Number ofShares, Forfeited/Expired	(3,069)
Number ofShares, Outstanding	15,779
Number of Shares, Vested and expected to vest, April 30, 2013	14,952
Number of Shares, Exercisable, April 30, 2013	12,731
Weighted-average, Exercise Price, Outstanding	$ 29.54
Weighted-average, Exercise Price, Granted	$ 4.50
Weighted-average, Exercise Price, Exercised	$ 0
Weighted-average, Exercise Price, Forfeited/Expired	$ 37.54
Weighted-average, Exercise Price, Outstanding	$ 7.58
Weighted-average, Exercise Price, Vested and expected to vest, April 30, 2013	$ 7.64
Weighted-average, Exercise Price, Exercisable, April 30, 2013	$ 7.83
Weighted- average Remaining Contractual Term, Outstanding, April 30, 2013	3 years 9 months 18 days
Weighted- average Remaining Contractual Term, Vested and expected to vest, April 30, 2013	3 years 9 months 18 days
Weighted- average Remaining Contractual Term, Exercisable, April 30, 2013	3 years 8 months 12 days
Aggregate Intrinsic Value, Outstanding, April 30, 2013	$ 0
Aggregate Intrinsic Value, Vested and expected to vest, April 30, 2013	0
Aggregate Intrinsic Value, Exercisable, April 30, 2013	0
2006 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number ofShares, Outstanding	757
Number ofShares, Granted	46,571
Number ofShares, Exercised	0
Number ofShares, Forfeited/Expired	(757)
Number ofShares, Outstanding	46,571
Number of Shares, Vested and expected to vest, April 30, 2013	46,571
Number of Shares, Exercisable, April 30, 2013	46,571
Weighted-average, Exercise Price, Outstanding	$ 77.08
Weighted-average, Exercise Price, Granted	$ 4.19
Weighted-average, Exercise Price, Exercised	$ 0
Weighted-average, Exercise Price, Forfeited/Expired	$ 77.08
Weighted-average, Exercise Price, Outstanding	$ 4.19
Weighted-average, Exercise Price, Vested and expected to vest, April 30, 2013	$ 4.19
Weighted-average, Exercise Price, Exercisable, April 30, 2013	$ 4.19
Weighted- average Remaining Contractual Term, Outstanding, April 30, 2013	4 years 4 months 24 days
Weighted- average Remaining Contractual Term, Vested and expected to vest, April 30, 2013	4 years 4 months 24 days
Weighted- average Remaining Contractual Term, Exercisable, April 30, 2013	4 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding, April 30, 2013	0
Aggregate Intrinsic Value, Vested and expected to vest, April 30, 2013	0
Aggregate Intrinsic Value, Exercisable, April 30, 2013	0
2007 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number ofShares, Outstanding	27,071
Number ofShares, Granted	37,714
Number ofShares, Exercised	0
Number ofShares, Forfeited/Expired	(10,856)
Number ofShares, Outstanding	53,929
Number of Shares, Vested and expected to vest, April 30, 2013	52,379
Number of Shares, Exercisable, April 30, 2013	48,214
Weighted-average, Exercise Price, Outstanding	$ 26.81
Weighted-average, Exercise Price, Granted	$ 3.82
Weighted-average, Exercise Price, Exercised	$ 0
Weighted-average, Exercise Price, Forfeited/Expired	$ 37.40
Weighted-average, Exercise Price, Outstanding	$ 8.60
Weighted-average, Exercise Price, Vested and expected to vest, April 30, 2013	$ 8.78
Weighted-average, Exercise Price, Exercisable, April 30, 2013	$ 9.30
Weighted- average Remaining Contractual Term, Outstanding, April 30, 2013	3 years 6 months
Weighted- average Remaining Contractual Term, Vested and expected to vest, April 30, 2013	3 years 4 months 24 days
Weighted- average Remaining Contractual Term, Exercisable, April 30, 2013	3 years 3 months 18 days
Aggregate Intrinsic Value, Outstanding, April 30, 2013	0
Aggregate Intrinsic Value, Vested and expected to vest, April 30, 2013	0
Aggregate Intrinsic Value, Exercisable, April 30, 2013	$ 0

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-SubTopic 10

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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-Name Accounting Standards Codification

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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Weighted average remaining contractual term for fully vested and expected to vest options that are exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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Number of share options (or share units) exercised during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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