Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2018

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, 2018 Using
	As of March 31, 2018			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	$	4,934		$	4,934	$	—		$	—	Cash and cash equivalents
Foreign government treasury bills	49			49		—			—		Cash and cash equivalents
U.S. treasuries and government agency securities	75			75		—			—		Other current assets
Foreign currency forward contracts not designated as hedges	3			—		3			—		Other current assets
Total recurring fair value measurements	$	5,061		$	5,058	$	3		$	—
Financial liabilities:
Foreign currency forward contracts designated as hedges	$	(22	)	$	—	$	(22	)	$	—	Accrued expenses and other liabilities

				Fair Value Measurements at December 31, 2017 Using
	As of December 31, 2017			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	$	4,405		$	4,405	$	—		$	—	Cash and cash equivalents
Foreign government treasury bills	39			39		—			—		Cash and cash equivalents
U.S. treasuries and government agency securities	55			55		—			—		Other current assets
Total recurring fair value measurements	$	4,499		$	4,499	$	—		$	—
Financial liabilities:
Foreign currency forward contracts designated as hedges	$	(5	)	$	—	$	(5	)	$	—	Accrued expenses and other liabilities

Foreign currency forward contracts

The total 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, 2018				As of December 31, 2017
	Notional amount		Fair value gain (loss)		Notional amount		Fair value gain (loss)
Foreign Currency:
Buy Euro, Sell USD	$	137	$	3	$	—	$	—

The total gross notional amounts and fair values of our Cash Flow Hedges are as follows (amounts in millions):

	As of March 31, 2018					As of December 31, 2017
	Notional amount		Fair value gain (loss)			Notional amount		Fair value gain (loss)
Foreign Currency:
Buy USD, Sell Euro	$	610	$	(22	)	$	521	$	(5	)

Net realized gains (losses) reclassified out of accumulated other comprehensive income (loss)

The amount of pre-tax net realized gains (losses) associated with our Cash Flow Hedges that were reclassified out of “Accumulated other comprehensive income (loss)” and into earnings was as follows (amounts in millions):

	For the Three Months Ended March 31,
	2018			2017		Statement of Operations Classification
Cash Flow Hedges	$	(10	)	$	6	Net revenues