Marketable Investment Securities - Schedule of Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Available-for-sale debt securities:
Total available-for-sale debt securities	$ 880,815	$ 1,622,926
Equity securities	142,943	24,435
Total marketable investment securities, including restricted amounts	1,023,758	1,647,361
Less: Restricted marketable investment securities	(13,262)	(9,090)
Marketable investment securities	1,010,496	1,638,271
Corporate bonds
Available-for-sale debt securities:
Total available-for-sale debt securities	289,784	372,746
Commercial paper
Available-for-sale debt securities:
Total available-for-sale debt securities	498,358	1,101,888
Other debt securities
Available-for-sale debt securities:
Total available-for-sale debt securities	$ 92,673	$ 148,292

Amount 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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