Fair Value Measurements - Reconciliation of Changes in Debt Securities (Details) $ in Thousands	3 Months Ended
Apr. 26, 2020 USD ($)
Debt Securities, Available For Sale, Reconciliation [Roll Forward]
Balance at January 26, 2020	$ 10,700
Additions	550
Increase in credit loss reserve	(2,022)
Interest accrued	253
Balance at April 26, 2020	$ 9,481

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

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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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-Publisher FASB
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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.

+ References

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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.

+ References

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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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