Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Fair value, assets measured on a recurring and/or non-recurring basis

The table below segregates all of our financial assets and liabilities that are measured at fair value on a recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to determine the fair value at the measurement date (amounts in millions):

			Fair Value Measurements at March 31, 2021 Using
	As of March 31, 2021		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance Sheet Classification
Financial Assets:
Recurring fair value measurements:
Money market funds	$	8,968	$	8,968	$	—	$	—	Cash and cash equivalents
Foreign government treasury bills	25		25		—		—		Cash and cash equivalents
U.S. treasuries and government agency securities	227		227		—		—		Other current assets
Foreign currency forward contracts designated as hedges	12		—		12		—		Other current assets and Other assets
Total	$	9,232	$	9,220	$	12	$	—
Financial Liabilities:
Foreign currency forward contracts not designated as hedges	$	(1)	$	—	$	(1)	$	—	Accrued expenses and other liabilities
Foreign currency forward contracts designated as hedges	(7)		—		(7)		—		Accrued expenses and other liabilities
Total	$	(8)	$	—	$	(8)	$	—

			Fair Value Measurements at December 31, 2020 Using
	As of December 31, 2020		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Balance Sheet Classification
Financial Assets:
Recurring fair value measurements:
Money market funds	$	8,345	$	8,345	$	—	$	—	Cash and cash equivalents
Foreign government treasury bills	34		34		—		—		Cash and cash equivalents
U.S. treasuries and government agency securities	164		164		—		—		Other current assets
Total	$	8,543	$	8,543	$	—	$	—
Financial Liabilities:
Foreign currency forward contracts not designated as hedges	$	(2)	$	—	$	(2)	$	—	Accrued expenses and other liabilities
Foreign currency forward contracts designated as hedges	(24)		—		(24)		—		Accrued expenses and other liabilities
Total	$	(26)	$	—	$	(26)	$	—

Foreign currency forward contracts

The total gross notional amounts and fair values of our Cash Flow Hedges, all of which have remaining maturities of 19 months or less as of March 31, 2021, are as follows (amounts in millions):

	As of March 31, 2021				As of December 31, 2020
	Notional amount		Fair value gain (loss)		Notional amount		Fair value gain (loss)
Foreign Currency:
Buy USD, Sell Euro	$	850	$	5	$	542	$	(24)

The gross notional amounts and fair values of our foreign currency forward contracts not designated as hedges are as follows (amounts in millions):

	As of March 31, 2021				As of December 31, 2020
	Notional amount		Fair value gain (loss)		Notional amount		Fair value gain (loss)
Foreign Currency:
Buy USD, Sell GBP	$	148	$	(1)	$	116	$	(2)