CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($)		3 Months Ended		9 Months Ended
		Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2018	Jan. 31, 2017
Income Statement [Abstract]
Contract manufacturing revenue		$ 6,819,000	$ 10,747,000	$ 46,678,000	$ 39,726,000
Cost of contract manufacturing		10,951,000	7,974,000	47,641,000	26,477,000
Gross profit (loss)		(4,132,000)	2,773,000	(963,000)	13,249,000
Operating expenses:
Selling, general and administrative		4,824,000	4,365,000	12,273,000	13,602,000
Restructuring charges		0	0	1,258,000	0
Total operating expenses		4,824,000	4,365,000	13,531,000	13,602,000
Operating loss		(8,956,000)	(1,592,000)	(14,494,000)	(353,000)
Other income (expense):
Interest and other income		42,000	25,000	83,000	71,000
Interest and other expense		(14,000)	(2,000)	(18,000)	(2,000)
Loss from continuing operations		(8,928,000)	(1,569,000)	(14,429,000)	(284,000)
Loss from discontinued operations		(2,076,000)	(6,205,000)	(10,404,000)	(22,603,000)
Net loss		(11,004,000)	(7,774,000)	(24,833,000)	(22,887,000)
Comprehensive loss		(11,004,000)	(7,774,000)	(24,833,000)	(22,887,000)
Series E preferred stock accumulated dividends		(1,442,000)	(1,442,000)	(3,604,000)	(3,558,000)
Net loss attributable to common stockholders		$ (12,446,000)	$ (9,216,000)	$ (28,437,000)	$ (26,445,000)
Basic and diluted weighted average common shares outstanding	[1]	45,225,804	37,258,794	45,032,335	35,486,782
Basic and diluted net loss per common share attributable to common stockholders - Continuing operations		$ (0.23)	$ (0.08)	$ (0.40)	$ (0.11)
Basic and diluted net loss per common share attributable to common stockholders - Discontinued operations		(.05)	(.17)	(0.23)	(.64)
Net loss per share attributable to common stockholders	[1]	$ (.28)	$ (.25)	$ (0.63)	$ (0.75)

[1] All share and per share amounts of our common stock for all prior fiscal year periods presented have been retroactively adjusted to reflect the one-for-seven reverse stock split of our issued and outstanding common stock, which took effect on July 10, 2017 (Note 1).