Fair Value Measurements - Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Jul. 31, 2022	Jul. 31, 2021
Financial Assets:
Short-term investments:	$ 921,429	$ 928,006
Recurring
Financial Assets:
Total measured at fair value	1,177,152	1,032,588
Cash	147,127	181,141
Total cash, cash equivalents and short-term investments	1,324,279	1,213,729
Recurring \| U.S. Government securities
Financial Assets:
Short-term investments:	194,667	67,230
Recurring \| Corporate bonds
Financial Assets:
Cash equivalents:		2,002
Short-term investments:	409,024	513,688
Recurring \| Commercial paper
Financial Assets:
Cash equivalents:	27,927	29,997
Short-term investments:	317,738	347,088
Recurring \| Money market funds
Financial Assets:
Cash equivalents:	227,796	72,583
Recurring \| Level I
Financial Assets:
Total measured at fair value	227,796	72,583
Recurring \| Level I \| U.S. Government securities
Financial Assets:
Short-term investments:	0	0
Recurring \| Level I \| Corporate bonds
Financial Assets:
Cash equivalents:		0
Short-term investments:	0	0
Recurring \| Level I \| Commercial paper
Financial Assets:
Cash equivalents:	0	0
Short-term investments:	0	0
Recurring \| Level I \| Money market funds
Financial Assets:
Cash equivalents:	227,796	72,583
Recurring \| Level II
Financial Assets:
Total measured at fair value	949,356	960,005
Recurring \| Level II \| U.S. Government securities
Financial Assets:
Short-term investments:	194,667	67,230
Recurring \| Level II \| Corporate bonds
Financial Assets:
Cash equivalents:		2,002
Short-term investments:	409,024	513,688
Recurring \| Level II \| Commercial paper
Financial Assets:
Cash equivalents:	27,927	29,997
Short-term investments:	317,738	347,088
Recurring \| Level II \| Money market funds
Financial Assets:
Cash equivalents:	0	0
Recurring \| Level III
Financial Assets:
Total measured at fair value	0	0
Recurring \| Level III \| U.S. Government securities
Financial Assets:
Short-term investments:	0	0
Recurring \| Level III \| Corporate bonds
Financial Assets:
Cash equivalents:		0
Short-term investments:	0	0
Recurring \| Level III \| Commercial paper
Financial Assets:
Cash equivalents:	0	0
Short-term investments:	0	0
Recurring \| Level III \| Money market funds
Financial Assets:
Cash equivalents:	$ 0	$ 0

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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