Fair Value Measurements

The FASB literature regarding fair value measurements for certain assets and liabilities establishes a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. This hierarchy requires entities to maximize the use of “observable inputs” and minimize the use of “unobservable inputs.” The three levels of inputs used to measure fair value are as follows:


•	Level 1—Quoted prices in active markets for identical assets or liabilities;


•	Level 2—Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets or liabilities in active markets or other inputs that are observable or can be corroborated by observable market data; and


•	Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities, including certain pricing models, discounted cash flow methodologies, and similar techniques that use significant unobservable inputs.

Fair Value Measurements on a 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 December 31, 2018 Using
	As of December 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	$	3,925		$	3,925	$	—		$	—	Cash and cash equivalents
Foreign government treasury bills	32			32		—			—		Cash and cash equivalents
U.S. treasuries and government agency securities	150			150		—			—		Other current assets
Foreign currency forward contracts designated as hedges	13			—		13			—		Other current assets
Foreign currency forward contracts not designated as hedges	1			—		1			—		Other current assets
Total recurring fair value measurements	$	4,121		$	4,107	$	14		$	—

Financial Liabilities:
Foreign currency forward contracts designated as hedges	$	(1	)	$	—	$	(1	)	$	—	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

Foreign Currency Forward Contracts Designated as Hedges (“Cash Flow Hedges”)

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



	As of December 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	$	723	$	12	$	521	$	(5	)

At December 31, 2018, our Cash Flow Hedges have remaining maturities of 12 months or less. Additionally, $11 million of net realized but unrecognized gains are recorded within “Accumulated other comprehensive income (loss)” at December 31, 2018, for Cash Flow Hedges that had settled but were deferred and will be amortized into earnings, along with the associated hedged revenues. Such amounts will be reclassified into earnings within the next 12 months.

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 Years Ended December 31,
	2018		2017			2016		Statement of Operations Classification
Cash Flow Hedges	$	7	$	(1	)	$	4	Net revenues

Foreign Currency Forward Contracts Not Designated as Hedges

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 December 31, 2018				As of December 31, 2017
	Notional amount		Fair value gain (loss)		Notional amount		Fair value gain (loss)
Foreign Currency:
Buy USD, Sell GBP	$	55	$	1	$	—	$	—

During the years ended December 31, 2018, 2017, and 2016 pre-tax net gains associated with these forward contracts were recorded in “General and administrative expenses” and were not material.

Fair Value Measurements on a Non-Recurring Basis

We measure the fair value of certain assets on a non-recurring basis, generally annually or when events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable.

For the years ended December 31, 2018, 2017, and 2016, there were no impairment charges related to assets that are measured on a non-recurring basis.