Fair Value Measurements (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2017

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value of Financial Assets and Liabilities

The fair value of certain financial instruments and the hierarchy level we used to estimate fair values are shown below:

	March 31, 2017
			Hierarchy Level
	Carrying Value		Level 1		Level 2		Level 3
	(in millions)
Assets:
Cash equivalents	$	580	$	—	$	580	$	—
Restricted cash equivalents		12		—		12		—
Liabilities:
Long-term debt(1)		6,370		2,512		—		3,996
Interest rate swaps		7		—		7		—

	December 31, 2016
			Hierarchy Level
	Carrying Value		Level 1		Level 2		Level 3
	(in millions)
Assets:
Cash equivalents	$	782	$	—	$	782	$	—
Restricted cash equivalents		11		—		11		—
Liabilities:
Long-term debt(1)		6,369		2,516		—		4,006
Interest rate swaps		12		—		12		—

⁽¹⁾  Carrying value includes unamortized deferred financing costs and discount. The carrying values and fair values exclude capital lease obligations and other debt.

e did not elect the fair value measurement option for any of our financial assets or liabilities. The fair value of certain financial instruments and the hierarchy level we used to estimate fair values are shown below:

	December 31, 2016
	Carrying Value		Hierarchy Level
			Level 1		Level 2		Level 3
	(in millions)
Assets:
Cash equivalents	$	782	$	—	$	782	$	—
Restricted cash equivalents		11		—		11		—
Liabilities:
Long-term debt(1)		6,369		2,516		—		4,006
Interest rate swaps		12		—		12		—

	December 31, 2015
	Carrying Value		Hierarchy Level
			Level 1		Level 2		Level 3
	(in millions)
Assets:
Cash equivalents	$	287	$	—	$	287	$	—
Restricted cash equivalents		18		—		18		—
Liabilities:
Long-term debt(1)		5,647		1,560		—		4,222
Interest rate swaps		15		—		15		—

⁽¹⁾  The carrying value includes unamortized deferred financing costs and discount. The carrying values and fair values exclude capital lease obligations and other debt.