Fair Value Measurements - Reconciliation of Changes in Debt Securities (Details) $ in Thousands	12 Months Ended
Jan. 31, 2021 USD ($)
Debt Securities, Available For Sale, Reconciliation [Roll Forward]
Beginning Balance	$ 10,700
Additions	3,500
Fair market value adjustment to OCI	(313)
Increase in credit loss reserve	(2,927)
Interest accrued	1,029
Ending Balance	$ 11,989

Debt Securities, Available For Sale, Reconciliation [Roll Forward]

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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).

+ References

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Amount of increase (decrease) in 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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Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows.

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Amount of interest income on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows, attributable to passage of time.

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Amount of cash outflow to acquire 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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