Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis

Our assets and liabilities that were measured at fair value on a recurring basis were as follows (in millions):

	December 31, 2021								December 31, 2020
	Fair Value		Level I		Level II		Level III		Fair Value		Level I		Level II		Level III
Money market funds (cash    and cash equivalents)	$	9,548	$	9,548	$	—	$	—	$	13,847	$	13,847	$	—	$	—
Corporate debt securities    (short-term marketable    securities)		131		—		131		—		—		—		—		—
Interest rate swap liabilities		31		—		31		—		58		—		58		—
Total	$	9,710	$	9,548	$	162	$	—	$	13,905	$	13,847	$	58	$	—

Schedule of Interest Rate Swaps Outstanding

Our interest rate swaps outstanding were as follows (in millions):

	December 31, 2021						December 31, 2020
	Aggregate Notional Amount		Gross Asset at Fair Value		Gross Liability at Fair Value		Aggregate Notional Amount		Gross Asset at Fair Value		Gross Liability at Fair Value
Interest rate swaps	$	312	$	—	$	31	$	554	$	—	$	58

Our interest rate swaps activity was as follows (in millions):

	Year Ended December 31,
	2021		2020		2019
Gross losses	$	9	$	42	$	51
Gross gains	$	22	$	6	$	11

Schedule of Estimated Fair Values and Carrying Values

The following table presents the estimated fair values and the carrying values (in millions):

	December 31, 2021				December 31, 2020
	Carrying Value		Fair Value		Carrying Value		Fair Value
Convertible Senior Notes (1)	$	119	$	2,016	$	1,971	$	24,596
2025 Notes (1)	$	—	$	—	$	1,785	$	1,877
Solar Asset and Loan-backed Notes	$	827	$	834	$	1,261	$	1,289

The 2021 Notes, our subsidiary’s 5.50% Convertible Senior Notes due in 2022 and the 2025 Notes were fully settled in 2021.