Marketable Investment Securities (Tables)

12 Months Ended

Dec. 31, 2021

Investments, Debt and Equity Securities [Abstract]

Schedule of Marketable Investment Securities

The following table presents our Marketable investment securities:

	As of December 31,
	2021		2020
Marketable investment securities:
Available-for-sale debt securities:
Corporate bonds	$	289,784	$	372,746
Commercial paper	498,358		1,101,888
Other debt securities	92,673		148,292
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)
Total marketable investment securities	$	1,010,496	$	1,638,271

Schedule of Available-for-sale Securities Reconciliation

The following table presents the components of our available-for-sale debt securities:

	Amortized		Unrealized				Estimated
	Cost		Gains		Losses		Fair Value
As of December 31, 2021
Corporate bonds	$	290,169	$	—	$	(385)	$	289,784
Commercial paper	498,358		—		—		498,358
Other debt securities	92,742		—		(69)		92,673
Total available-for-sale debt securities	$	881,269	$	—	$	(454)	$	880,815
As of December 31, 2020
Corporate bonds	$	372,702	$	78	$	(34)	$	372,746
Commercial paper	1,101,888		—		—		1,101,888
Other debt securities	148,292		6		(6)		148,292
Total available-for-sale debt securities	$	1,622,882	$	84	$	(40)	$	1,622,926

Schedule of Activity on Available-for-sale Debt Securities

The following table presents the activity on our available-for-sale debt securities:

	For the years ended December 31,
	2021		2020		2019
Proceeds from sales	$	410,918	$	160,494	$	435,978
Gains (losses) on sales, net	$	12	$	2	$	549

Schedule of Fair Value Option Corporate Bonds

The following table presents the activity on our fair value option corporate bonds:

	For the years ended December 31,
	2021		2020		2019
Proceeds from sales	$	—	$	32,054	$	46,717
Gains (losses) on investments, net	$	—	$	14,980	$	6,746

Schedule of Activity of Equity Securities

The following table presents the activity of our equity securities:

	For the years ended December 31,
	2021		2020		2019
Proceeds from sales	$	832	$	14,401	$	104,729
Gains (losses) on investments, net	$	49,391	$	(3,241)	$	53,873

Schedule of Fair Value Measurements

The following table presents our marketable investment securities categorized by the fair value hierarchy, certain of which have historically experienced volatility:

	Level 1		Level 2		Total
As of December 31, 2021
Cash equivalents (including restricted)	$	7,872	$	423,123	$	430,995
Available-for-sale debt securities:
Corporate bonds	$	—	$	289,784	$	289,784
Commercial paper	—		498,358		498,358
Other debt securities	14,274		78,399		92,673
Total available-for-sale debt securities	14,274		866,541		880,815
Equity securities	131,413		11,530		142,943
Total marketable investment securities, including restricted amounts	145,687		878,071		1,023,758
Less: Restricted marketable investment securities	(13,262)		—		(13,262)
Total marketable investment securities	$	132,425	$	878,071	$	1,010,496
As of December 31, 2020
Cash equivalents (including restricted)	$	416	$	809,698	$	810,114
Available-for-sale debt securities:
Corporate bonds	$	—	$	372,746	$	372,746
Commercial paper	—		1,101,888		1,101,888
Other debt securities	139,486		8,806		148,292
Total available-for-sale debt securities	139,486		1,483,440		1,622,926
Equity securities	14,441		9,994		24,435
Total marketable investment securities, including restricted amounts	153,927		1,493,434		1,647,361
Less: Restricted marketable investment securities	(9,090)		—		(9,090)
Total marketable investment securities	$	144,837	$	1,493,434	$	1,638,271