CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock
Balance at Apr. 30, 2021	$ 279,905	$ 14	$ 265,362	$ 14,529
Balance, shares at Apr. 30, 2021		14,059,000
Net income (loss)	11,806			11,806
Stock-based compensation	2,336		2,336
Shares issued under employee stock purchase plan	408		408
Shares issued under employee stock purchase plan, shares		35,000
Proceeds from exercise of stock options	5		5
Proceeds from exercise of stock options, shares		3,000
Issuance of common stock under restricted stock unit awards, net of tax	(528)		(528)
Issuance of common stock under restricted stock unit awards, net of tax, shares		91,000
Repurchase of treasury stock	(7,011)				$ (7,011)
Repurchase of treasury stock, shares					364,000
Balance at Jan. 31, 2022	286,921	$ 14	267,583	26,335	$ (7,011)
Balance, shares at Jan. 31, 2022		14,188,000			364,000
Balance at Oct. 31, 2021	289,269	$ 14	266,686	22,569
Balance, shares at Oct. 31, 2021		14,183,000
Net income (loss)	3,766			3,766
Stock-based compensation	920		920
Issuance of common stock under restricted stock unit awards, net of tax	(23)		(23)
Issuance of common stock under restricted stock unit awards, net of tax, shares		5,000
Repurchase of treasury stock	(7,011)				$ (7,011)
Repurchase of treasury stock, shares					364,000
Balance at Jan. 31, 2022	286,921	$ 14	267,583	26,335	$ (7,011)
Balance, shares at Jan. 31, 2022		14,188,000			364,000
Balance at Apr. 30, 2022	$ 203,031	$ 14	268,393	(50,351)	$ (15,025)
Balance, shares at Apr. 30, 2022	13,403,326	14,240,000			837,000
Net income (loss)	$ (8,188)			(8,188)
Stock-based compensation	2,900		2,900
Shares issued under employee stock purchase plan	287		287
Shares issued under employee stock purchase plan, shares		39,000
Issuance of common stock under restricted stock unit awards, net of tax	(304)		(304)
Issuance of common stock under restricted stock unit awards, net of tax, shares		90,000
Repurchase of treasury stock	(2,568)				$ (2,568)
Repurchase of treasury stock, shares					276,000
Balance at Jan. 31, 2023	$ 195,158	$ 14	271,276	(58,539)	$ (17,593)
Balance, shares at Jan. 31, 2023	13,256,830	14,369,000			1,113,000
Balance at Oct. 31, 2022	$ 198,777	$ 14	270,220	(55,676)	$ (15,781)
Balance, shares at Oct. 31, 2022		14,353,000			921,000
Net income (loss)	(2,863)			(2,863)
Stock-based compensation	1,065		1,065
Issuance of common stock under restricted stock unit awards, net of tax	(9)		(9)
Issuance of common stock under restricted stock unit awards, net of tax, shares		16,000
Repurchase of treasury stock	(1,812)				$ (1,812)
Repurchase of treasury stock, shares					192,000
Balance at Jan. 31, 2023	$ 195,158	$ 14	$ 271,276	$ (58,539)	$ (17,593)
Balance, shares at Jan. 31, 2023	13,256,830	14,369,000			1,113,000