Cash and Cash Equivalents, Investments and Restricted Cash - Available-for-sale Investments By Contractual Maturity Date (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Amortized Cost
Due in one year or less	$ 180,857
Due after one year	401,043
Amortized Cost	581,900
Estimated Fair Market Value
Due in one year or less	180,549
Due after one year	408,476
Total	$ 589,025

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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