CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($)	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock
Balance at Apr. 30, 2021	$ 279,905,000	$ 14,000	$ 265,362,000	$ 14,529,000
Balance, shares at Apr. 30, 2021		14,059,000
Net income (loss)	8,040,000			8,040,000
Stock-based compensation	1,416,000		1,416,000
Shares issued under employee stock purchase plan	408,000		408,000
Shares issued under employee stock purchase plan, shares		35,000
Proceeds from exercise of stock options	5,000		5,000
Proceeds from exercise of stock options, shares		3,000
Issuance of common stock under restricted stock unit awards, net of tax	(505,000)		(505,000)
Issuance of common stock under restricted stock unit awards, net of tax, shares		86,000
Balance at Oct. 31, 2021	289,269,000	$ 14,000	266,686,000	22,569,000
Balance, shares at Oct. 31, 2021		14,183,000
Balance at Jul. 31, 2021	283,807,000	$ 14,000	265,807,000	17,986,000
Balance, shares at Jul. 31, 2021		14,100,000
Net income (loss)	4,583,000			4,583,000
Stock-based compensation	664,000		664,000
Shares issued under employee stock purchase plan	408,000		408,000
Shares issued under employee stock purchase plan, shares		35,000
Issuance of common stock under restricted stock unit awards, net of tax	(193,000)		(193,000)
Issuance of common stock under restricted stock unit awards, net of tax, shares		48,000
Balance at Oct. 31, 2021	289,269,000	$ 14,000	266,686,000	22,569,000
Balance, shares at Oct. 31, 2021		14,183,000
Balance at Apr. 30, 2022	$ 203,031,000	$ 14,000	268,393,000	(50,351,000)	$ (15,025,000)
Balance, shares at Apr. 30, 2022	13,403,326	14,240,000			837,000
Net income (loss)	$ (5,325,000)			(5,325,000)
Stock-based compensation	1,835,000		1,835,000
Shares issued under employee stock purchase plan	287,000		287,000
Shares issued under employee stock purchase plan, shares		39,000
Issuance of common stock under restricted stock unit awards, net of tax	(295,000)		(295,000)
Issuance of common stock under restricted stock unit awards, net of tax, shares		74,000
Repurchase of treasury stock	(756,000)				$ (756,000)
Repurchase of treasury stock, shares					84,000
Balance at Oct. 31, 2022	$ 198,777,000	$ 14,000	270,220,000	(55,676,000)	$ (15,781,000)
Balance, shares at Oct. 31, 2022	13,432,177	14,353,000			921,000
Balance at Jul. 31, 2022	$ 197,798,000	$ 14,000	268,855,000	(56,046,000)	$ (15,025,000)
Balance, shares at Jul. 31, 2022		14,292,000			837,000
Net income (loss)	370,000			370,000
Stock-based compensation	1,121,000		1,121,000
Shares issued under employee stock purchase plan	287,000		287,000
Shares issued under employee stock purchase plan, shares		39,000
Issuance of common stock under restricted stock unit awards, net of tax	(43,000)		(43,000)
Issuance of common stock under restricted stock unit awards, net of tax, shares		22,000
Repurchase of treasury stock	(756,000)				$ (756,000)
Repurchase of treasury stock, shares					84,000
Balance at Oct. 31, 2022	$ 198,777,000	$ 14,000	$ 270,220,000	$ (55,676,000)	$ (15,781,000)
Balance, shares at Oct. 31, 2022	13,432,177	14,353,000			921,000