v3.6.0.2

Debt (Textuals) (Details) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Prior Period Reclassification Adjustment							$ 152
Maximum Remaining Lease Term						35 years
Lease Assets, Historical Cost	$ 864			$ 877		$ 864	877
Lease Assets, Accumulated Depreciation	404			390		404	390
Gains (Losses) on Extinguishment of Debt						(25)	(40)	$ (346)
2017 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	550					$ 550
New 2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 562
2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 550			$ 550
First Lien Notes 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed						10.00%
Gains (Losses) on Extinguishment of Debt	(5)				$ (19)
Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Repayment time for drawings under letters of credit						2 days
Excess amount of asset sales requiring mandatory prepayments						$ 3,000
Corporate Revolving Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Applicable margin range percentage above base rate						1.00%
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates						2.00%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage						0.25%
Corporate Revolving Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Applicable margin range percentage above base rate						1.25%
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates						2.25%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage						0.50%
CDHI [Member]
Debt Instrument [Line Items]
Letter of Credit Total	$ 300					$ 300
One Month [Member] | Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Interest periods for LIBOR rate borrowings						1 month
Two Months [Member] | Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Interest periods for LIBOR rate borrowings						2 months
Three Months [Member] | Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Interest periods for LIBOR rate borrowings						3 months
Six Months [Member] | Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Interest periods for LIBOR rate borrowings						6 months
Nine Months [Member] | Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Interest periods for LIBOR rate borrowings						9 months
Twelve Months [Member] | Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Interest periods for LIBOR rate borrowings						12 months
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Increase (Decrease), Net			$ 178
Line of Credit Facility, Maximum Borrowing Capacity			1,678
Increase in Letter of Credit Sublimit			250
Total Letter of Credit Sublimit			$ 1,000
Extension of Line of Credit Revolver			2 years
Prime Rate Or The Eurodollar Rate For a One Month Interest Period [Member] | 2017 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.75%
Prime Rate Or The Eurodollar Rate For a One Month Interest Period [Member] | New 2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.00%
Prime Rate Or The Eurodollar Rate For a One Month Interest Period [Member] | 2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				2.00%
Federal Funds Effective Rate [Member] | 2017 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Federal Funds Effective Rate [Member] | New 2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.50%
Federal Funds Effective Rate [Member] | 2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				0.50%
Federal Funds Effective Rate [Member] | Corporate Revolving Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate						0.50%
Eurodollar Rate For A One-Month Interest Period [Member] | 2017 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Eurodollar Rate For A One-Month Interest Period [Member] | New 2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.00%
Eurodollar Rate For A One-Month Interest Period [Member] | 2023 First Lien Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate				1.00%

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