Debt Obligations - Short-term Borrowings and Long-term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019	Aug. 21, 2019
Debt Instrument [Line Items]
Short-term Debt	$ 222	$ 282
Long-term debt	4,266	3,277
Unamortized Debt Issuance Expense	(42)	(32)
Term loan facility
Debt Instrument [Line Items]
Long-term debt	$ 735	$ 740
Weighted-average interest rate on long-term debt	2.65%	4.30%
Revolving credit facility
Debt Instrument [Line Items]
Long-term debt	$ 1,070	$ 265
Weighted-average interest rate on long-term debt	2.16%	3.76%
5.00% Senior Notes due 2022
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 600
Debt stated interest rate	500.00%	500.00%
6.375% Senior Notes due 2023
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 700
Debt stated interest rate	6.375%	6.375%
8.125% Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt stated interest rate	8.125%
8.125% Notes due 2025 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 400	$ 0
5.750% Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 500	$ 500
Debt stated interest rate	5.75%	5.75%	5.75%
5.000% Senior Notes due 2028
Debt Instrument [Line Items]
Long-term debt	$ 650	$ 0
Debt stated interest rate	5.00%
6.125% Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 500	$ 500
Debt stated interest rate	6.125%	6.125%	6.125%
5.250% Senior Notes due 2030
Debt Instrument [Line Items]
Long-term debt	$ 450	$ 0
Debt stated interest rate	5.25%	5.25%
Other
Debt Instrument [Line Items]
Long-term debt	$ 3	$ 4
Weighted-average interest rate on long-term debt	7.02%	0.05%
Term loan facility
Debt Instrument [Line Items]
Current portion of Senior Secured Credit Facility	$ 8	$ 8
Weighted-Average interest rate on short-term borrowings	2.65%	4.30%
Trade Receivables Securitization Facility
Debt Instrument [Line Items]
Short-term Debt	$ 212	$ 270
Weighted-Average interest rate on short-term borrowings	0.99%	2.65%
Other
Debt Instrument [Line Items]
Short-term Debt	$ 2	$ 4
Weighted-Average interest rate on short-term borrowings	8.06%	2.82%

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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