Investment Securities - Summary of Investment Securities (Details) - USD ($)	Aug. 29, 2020	Feb. 29, 2020
Available-for-sale securities:
Long term	$ 19,800,000	$ 20,300,000
Held-to-maturity securities:
Short term	0	385,600,000
Total investment securities	$ 19,800,000	$ 405,900,000

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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), classified as noncurrent.

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Amount of investment in debt security measured at amortized cost (held-to-maturity), classified as current.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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