v3.19.3

Debt (Debt Textuals) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Aug. 12, 2019	Apr. 05, 2019
Line of Credit Facility [Line Items]
Gain (Loss) on Extinguishment of Debt	$ (12)		$ (1)	$ (11)	$ (1)
Repayments of Other Long-term Debt				$ 311	$ 89
Debt Instruments [Abstract]
Debt Instrument, Interest Rate, Effective Percentage	5.90%		5.70%	5.90%	5.70%
CDHI [Member]
Line of Credit Facility [Line Items]
Future Line of Credit Facility Maximum Borrowing Capacity	$ 125			$ 125
Other Corporate Facilities [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	300			300
OMEC [Member]
Line of Credit Facility [Line Items]
Repayments of Other Long-term Debt	$ 198
New 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount						$ 750
Percentage of principal amount of Term Loan to be paid quarterly	0.25%
Debt Instrument Unamortized Discount Percent						0.50%
Debt Issuance Costs, Net						$ 11
2023 First Lien Term Loan and OMEC Project Debt [Member]
Line of Credit Facility [Line Items]
Gain (Loss) on Extinguishment of Debt	$ (12)
2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Face Amount							$ 950
Percentage of principal amount of Term Loan to be paid quarterly	0.25%
Debt Instrument Unamortized Discount Percent							1.00%
Debt Issuance Costs, Net							$ 7
Russell City and Los Esteros Project Debt [Member]
Line of Credit Facility [Line Items]
Long-term Debt, Excluding Current Maturities	$ 354			354
2019 and 2023 First Lien Term Loans [Member]
Line of Credit Facility [Line Items]
Gain (Loss) on Extinguishment of Debt	(3)
Amendment No. 6 [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Increase (Decrease), Net		$ 330
Line of Credit Facility, Maximum Borrowing Capacity							$ 2,020
Amendment No. 8 [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	1,690			$ 1,690
Amendment No. 10 [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Increase (Decrease), Net	$ 20
Line of Credit Facility, Maximum Borrowing Capacity						2,000
Total Letter of Credit Sub-limit						$ 150
Federal Funds Effective Rate [Member] | New 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Federal Funds Effective Rate [Member] | 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Eurodollar Rate For A One-Month Interest Period [Member] | New 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Eurodollar Rate For A One-Month Interest Period [Member] | 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Prime Rate or The Eurodollar Rate For A One-Month Interest Period [Member] | New 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.50%
Prime Rate or The Eurodollar Rate For A One-Month Interest Period [Member] | 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.75%
London Interbank Offered Rate (LIBOR) [Member] | New 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.50%
London Interbank Offered Rate (LIBOR) [Member] | 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.75%
Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] | New 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						0.00%
Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] | 2026 First Lien Term Loan [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage							0.00%

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