Summary of Changes in Valuation Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 11,540	$ 58,700	$ 74,170
Additions charged to costs and expenses	48	835
Deductions		(47,995)	(15,470)
Balance at end of year	$ 11,588	$ 11,540	$ 58,700