Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

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, generally including money market funds, treasury bills, available-for-sale and derivative financial instruments, and other investments (amounts in millions):



			Fair Value Measurements at December 31, 2016 Using
	As of December 31, 2016		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Balance Sheet Classification
	As of December 31, 2016		(Level 1)		(Level 2)		(Level 3)		Balance Sheet Classification
Financial Assets:
Recurring fair value measurements:
Money market funds	$	2,921	$	2,921	$	—	$	—	Cash and cash equivalents
Foreign government treasury bills	38		38		—		—		Cash and cash equivalents
Foreign currency forward contracts designated as hedges	22		—		22		—		Other current assets
Auction rate securities ("ARS")	9		—		—		9		Other assets
Total recurring fair value measurements	$	2,990	$	2,959	$	22	$	9



				Fair Value Measurements at December 31, 2015 Using
	As of December 31, 2015			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs			Significant Unobservable Inputs		Balance Sheet Classification
	As of December 31, 2015			(Level 1)		(Level 2)			(Level 3)		Balance Sheet Classification
Financial Assets:
Recurring fair value measurements:
Money market funds	$	1,613		$	1,613	$	—		$	—	Cash and cash equivalents
Foreign government treasury bills	34			34		—			—		Cash and cash equivalents
Foreign currency forward contracts not designated as hedges	11			—		11			—		Other current assets
ARS	9			—		—			9		Other assets
Total recurring fair value measurements	$	1,667		$	1,647	$	11		$	9

Financial Liabilities:
Foreign currency forward contracts designated as hedges	$	(4	)	$	—	$	(4	)	$	—	Accrued expenses and other liabilities