Condensed Consolidated Statement of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Balance at Apr. 30, 2022	$ 185,093	$ 25	$ 439,104	$ (250,175)	$ (3,861)
Balance, shares at Apr. 30, 2022		24,550,748
Issuance of common stock from equity incentive plans	168		168
Issuance of common stock from equity incentive plans, shares		20,124
Stock-based compensation expense	2,642		2,642
Net loss	(23,042)			(23,042)
Foreign currency translation gain (loss)	(403)				(403)
Unrealized holding gain from marketable securities	98				98
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	16				16
Balance at Jul. 31, 2022	164,572	$ 25	441,914	(273,217)	(4,150)
Balance, shares at Jul. 31, 2022		24,570,872
Balance at Apr. 30, 2022	185,093	$ 25	439,104	(250,175)	(3,861)
Balance, shares at Apr. 30, 2022		24,550,748
Net loss	(66,602)
Foreign currency translation gain (loss)	(573)
Unrealized holding gain from marketable securities	808
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	84
Balance at Jan. 31, 2023	184,441	$ 34	504,725	(316,777)	(3,541)
Balance, shares at Jan. 31, 2023		34,127,762
Balance at Jul. 31, 2022	164,572	$ 25	441,914	(273,217)	(4,150)
Balance, shares at Jul. 31, 2022		24,570,872
Issuance of common stock from equity incentive plans	168		168
Issuance of common stock from equity incentive plans, shares		31,151
Stock-based compensation expense	2,506		2,506
Net loss	(22,257)			(22,257)
Foreign currency translation gain (loss)	(1,297)				(1,297)
Unrealized holding gain from marketable securities	52				52
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	69				69
Balance at Oct. 31, 2022	143,813	$ 25	444,588	(295,474)	(5,326)
Balance, shares at Oct. 31, 2022		24,602,023
Issuance of common stock from equity incentive plans	146		146
Issuance of common stock from equity incentive plans, shares		41,540
Issuance of common stock, net of issuance costs of $0.3 million	56,582	$ 9	56,573
Issuance of common stock, net of issuance costs of $0.3 million, shares		9,484,199
Issuance of pre-funded warrants for the purchase of common stock, net of issuance costs	1,085		1,085
Stock-based compensation expense	2,333		2,333
Net loss	(21,303)			(21,303)
Foreign currency translation gain (loss)	1,128				1,128
Unrealized holding gain from marketable securities	658				658
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	(1)				(1)
Balance at Jan. 31, 2023	184,441	$ 34	504,725	(316,777)	(3,541)
Balance, shares at Jan. 31, 2023		34,127,762
Balance at Apr. 30, 2023	161,025	$ 34	507,133	(343,082)	(3,060)
Balance, shares at Apr. 30, 2023		34,171,138
Issuance of common stock from equity incentive plans	204		204
Issuance of common stock from equity incentive plans, shares		35,313
Release of restricted stock units, shares		60,144
Stock-based compensation expense	3,254		3,254
Net loss	(25,317)			(25,317)
Foreign currency translation gain (loss)	91				91
Unrealized holding gain from marketable securities	392				392
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	(314)				(314)
Balance at Jul. 31, 2023	139,335	$ 34	510,591	(368,399)	(2,891)
Balance, shares at Jul. 31, 2023		34,266,595
Balance at Apr. 30, 2023	161,025	$ 34	507,133	(343,082)	(3,060)
Balance, shares at Apr. 30, 2023		34,171,138
Net loss	(81,995)
Foreign currency translation gain (loss)	(373)
Unrealized holding gain from marketable securities	1,270
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	(1,130)
Balance at Jan. 31, 2024	88,583	$ 34	516,920	(425,077)	(3,294)
Balance, shares at Jan. 31, 2024		34,595,623
Balance at Jul. 31, 2023	139,335	$ 34	510,591	(368,399)	(2,891)
Balance, shares at Jul. 31, 2023		34,266,595
Issuance of common stock from equity incentive plans	128		128
Issuance of common stock from equity incentive plans, shares		18,000
Release of restricted stock units, shares		136,863
Stock-based compensation expense	3,207		3,207
Net loss	(27,650)			(27,650)
Foreign currency translation gain (loss)	(419)				(419)
Unrealized holding gain from marketable securities	440				440
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	(595)				(595)
Balance at Oct. 31, 2023	114,446	$ 34	513,926	(396,049)	(3,465)
Balance, shares at Oct. 31, 2023		34,421,458
Issuance of common stock from equity incentive plans	283		283
Issuance of common stock from equity incentive plans, shares		36,914
Release of restricted stock units, shares		137,251
Stock-based compensation expense	2,711		2,711
Net loss	(29,028)			(29,028)
Foreign currency translation gain (loss)	(46)				(46)
Unrealized holding gain from marketable securities	438				438
Reclassification adjustment for realized (gain) loss on marketable securities included in net loss	(221)				(221)
Balance at Jan. 31, 2024	$ 88,583	$ 34	$ 516,920	$ (425,077)	$ (3,294)
Balance, shares at Jan. 31, 2024		34,595,623