Cash Equivalents and Investments - Narrative (Details)	12 Months Ended
Jan. 31, 2022 USD ($) investment	Jan. 31, 2021 USD ($) investment	Jan. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract]
Unsettled purchases of short-term investments	$ 0	$ 0
Unsettled maturities of short-term investments	0	31,000,000
Interest receivable	$ 6,000,000	$ 10,500,000
Number of short-term investments in unrealized loss positions \| investment	193	10
Gross unrealized gains or losses from available-for-sale securities			$ 0
Realized gains or losses reclassified out of accumulated other comprehensive income	$ 0	$ 0	$ 0
Other-than-temporary impairment short term investment	0	0
Strategic investments without a readily determinable fair value	15,300,000	$ 3,100,000
Strategic investments, realized gains and unrealized adjustments	$ 7,600,000

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Short-Term Investment Purchases Not Yet Settled

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in equity security without readily determinable fair value.

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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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