Cash Equivalents and Short-Term Investments - Schedule of Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Apr. 30, 2026	Jul. 31, 2025
Cash equivalents:
Amortized Cost	$ 835,742	$ 1,543,609
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	835,742	1,543,609
Short-term investments:
Amortized Cost	2,562,596	1,182,529
Unrealized Gains	1,726	1,894
Unrealized Losses	(7,327)	(1,037)
Fair Value	2,556,995	1,183,386
Total cash equivalents and short-term investments, amortized cost	3,398,338	2,726,138
Total cash equivalents and short-term investments, unrealized gains	1,726	1,894
Total cash equivalents and short-term investments, unrealized losses	(7,327)	(1,037)
Total cash equivalents and short-term investments	3,392,737	2,726,995
U.S. treasury securities
Short-term investments:
Amortized Cost	441,028	231,193
Unrealized Gains	241	56
Unrealized Losses	(1,369)	(250)
Fair Value	439,900	230,999
U.S. government agency securities
Short-term investments:
Amortized Cost	54,843	75,006
Unrealized Gains	10	26
Unrealized Losses	(163)	(40)
Fair Value	54,690	74,992
Corporate debt securities
Short-term investments:
Amortized Cost	1,748,998	876,330
Unrealized Gains	1,305	1,812
Unrealized Losses	(5,594)	(747)
Fair Value	1,744,709	877,395
Certificates of deposit
Short-term investments:
Amortized Cost	95,051
Unrealized Gains	0
Unrealized Losses	0
Fair Value	95,051
Asset-backed securities
Short-term investments:
Amortized Cost	217,664
Unrealized Gains	170
Unrealized Losses	(199)
Fair Value	217,635
Non-U.S. government securities
Short-term investments:
Amortized Cost	5,012
Unrealized Gains	0
Unrealized Losses	(2)
Fair Value	5,010
Money market funds
Cash equivalents:
Amortized Cost	788,013	1,403,678
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	788,013	1,403,678
Corporate debt securities
Cash equivalents:
Amortized Cost		8,468
Unrealized Gains		0
Unrealized Losses		0
Fair Value		8,468
Certificates of deposit
Cash equivalents:
Amortized Cost	47,729	131,463
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	$ 47,729	$ 131,463

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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Amount, before tax, of unrealized loss 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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amortized cost excluding accrued interest, after allowance for credit loss, of 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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