Stock Appreciation Rights (Details) (Stock Appreciation Rights (SARs) [Member], USD $)	6 Months Ended
	Oct. 31, 2012	Oct. 31, 2011
SARS Valuation Assumptions [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	320,000	280,000
Stock Appreciation Rights, Weighted Average Grant Price	$ 0.417	$ 0.428
Stock Appreciation Rights, Weighted Average Contractual Life Remaining	5.36	5.78
Stock Appreciation Rights, Weighted Average Market Price	$ 0.281	$ 0.430
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate	150.38%	127.90%
Weighted Average Expected Life	4.72	3.00
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.76%	1.06%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%	0.00%
Stock Appreciation Rights, Weighted Average Fair Value Price	$ 0.260	$ 0.406
Weighted Average Aggregate Fair Value	$ 56,000	$ 69,000
Weighted Average Aggregate Intrinsic Value	2,000	19,000
Stock Appreciation Rights, Compensation Expense	2,000	12,000
Unrecognized Compensation Expense Related to Non-Vested SARS Granted	15,000	22,000
Expected Period to Recognize Compensation Expense Related to Non-Vested SARSs Granted	2.08	2.08
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent	$ 61,000	$ 81,000
Maximum [Member]
SARS Valuation Assumptions [Line Items]
Stock Appreciation Rights, Upper Range of Grant Price	$ 0.695	$ 0.695
Minimum [Member]
SARS Valuation Assumptions [Line Items]
Stock Appreciation Rights, Lower Range of Grant Price	$ 0.208	$ 0.208