Investments - Contractual Maturity (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Amortized Cost
Within one year	$ 375,804
After one through five years	29,364
Amortized Cost	405,168
Fair Value
Within one year	375,927
After one through five years	29,333
Total available-for-sale securities	$ 405,260

Amortized cost 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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