CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Statement of Comprehensive Income [Abstract]
Net loss	$ (115,061)	$ (287,390)	$ (534,913)	$ (552,438)
Other comprehensive loss, net of tax:
Change in unrealized loss on available-for-sale securities, net of tax	(1,776)	(323)	(2,427)	(1,473)
Comprehensive loss	$ (116,837)	$ (287,713)	$ (537,340)	$ (553,911)