Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2022	Oct. 31, 2021	Oct. 31, 2022	Oct. 31, 2021
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ (19,809)	$ 756	$ (54,281)	$ (17,218)
Other comprehensive loss, net of tax:
Net change and reclassification of unrealized losses on investments	(1,041)	(608)	(1,043)	(1,219)
Other comprehensive loss, net of tax	(1,041)	(608)	(1,043)	(1,219)
Comprehensive income (loss)	$ (20,850)	$ 148	$ (55,324)	$ (18,437)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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