Financial Instruments - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Oct. 31, 2022	Oct. 31, 2021	Oct. 31, 2022	Oct. 31, 2021	Jan. 31, 2022
Investments, All Other Investments [Abstract]
Securities in continuous unrealized loss position for greater than twelve months	$ 0		$ 0		$ 0
Allowance for credit loss	0		0		0
Securities, writeoff			0	$ 0
Available-for-sale securities gross gains (losses)			0	0
Direct investments in privately held companies	181,000,000		181,000,000		$ 134,000,000
Equity method investment, realized gains on disposal	$ 0	$ 0	$ 1,000,000	$ 8,000,000

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of writeoff of allowance for credit loss 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 of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of realized gain (loss) 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 of gain (loss) on sale or disposal of an equity method investment.

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

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