Investments - Contractual Maturity (Details) $ in Thousands	Jun. 30, 2021 USD ($)
Amortized Cost
Within one year	$ 717,531
After one through five years	527,087
Amortized Cost	1,244,618
Fair Value
Within one year	717,285
After one through five years	525,436
Total available-for-sale securities	$ 1,242,721

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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