Short-Term and Long-Term Investments - Legal Maturities of Debt Investments (Details) $ in Thousands	Oct. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract]
Amortized Cost, Less than one year	$ 150,559
Amortized Cost, Due in 1-2 years	82,252
Amortized Cost	232,811
Estimated Fair Value, Less than one year	150,667
Estimated Fair Value, Due in 1-2 years	82,226
Estimated Fair Value	$ 232,893

Amortized cost 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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-Publisher FASB
-Name Accounting Standards Codification
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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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