Fair Value Measurements - Reconciliation of Changes in Debt Securities (Details) $ in Thousands	9 Months Ended
Oct. 31, 2021 USD ($)
Debt Securities, Available For Sale, Reconciliation [Roll Forward]
Balance at January 31, 2021	$ 11,989
Additions	450
Increase in credit loss reserve	(930)
Interest accrued	794
Conversion to equity	(626)
Balance at October 31, 2021	$ 11,677

Convertible Debt Investments, Converted To Equity During The Period

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- Definition

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

+ References

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- Definition

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 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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