Cash Equivalents and Short-Term Investments - Schedule of Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Jan. 31, 2023	Jul. 31, 2022
Cash equivalents:
Amortized Cost	$ 950,141	$ 692,188
Unrealized Gains	0	2
Unrealized Losses	(81)	(108)
Fair Value	950,060	692,082
Short-term investments:
Amortized Cost	658,389	730,014
Unrealized Gains	377	16
Unrealized Losses	(10,434)	(11,901)
Fair Value	648,332	718,129
Total cash equivalents and short-term investments, amortized cost	1,608,530	1,422,202
Total cash equivalents and short-term investments, unrealized gains	377	18
Total cash equivalents and short-term investments, unrealized losses	(10,515)	(12,009)
Total cash equivalents and short-term investments	1,598,392	1,410,211
U.S. treasury securities
Short-term investments:
Amortized Cost	31,533	96,089
Unrealized Gains	40	10
Unrealized Losses	0	(251)
Fair Value	31,573	95,848
U.S. government agency securities
Short-term investments:
Amortized Cost	276,278	339,957
Unrealized Gains	0	6
Unrealized Losses	(6,471)	(6,628)
Fair Value	269,807	333,335
Corporate debt securities
Short-term investments:
Amortized Cost	350,578	293,968
Unrealized Gains	337	0
Unrealized Losses	(3,963)	(5,022)
Fair Value	346,952	288,946
Money market funds
Cash equivalents:
Amortized Cost	436,581	247,613
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	436,581	247,613
U.S. treasury securities
Cash equivalents:
Amortized Cost	26,933	202,778
Unrealized Gains	0	0
Unrealized Losses	(2)	(70)
Fair Value	26,931	202,708
U.S. government agency securities
Cash equivalents:
Amortized Cost	369,324	135,525
Unrealized Gains	0	2
Unrealized Losses	(79)	(38)
Fair Value	369,245	135,489
Corporate debt securities
Cash equivalents:
Amortized Cost	117,303	106,272
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	$ 117,303	$ 106,272

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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