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Financial Derivative Instruments - Offsetting of Derivative Liabilities (Details) - Interest rate derivatives - USD ($) $ in Millions | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Accrued Liabilities [Member] |  |
Offsetting Liabilities [Line Items] |  |
Gross amounts of recognized liabilities | $ 20 | $ 2
Gross asset amounts offset in the Balance Sheet | 0 | 0
Liability derivative contracts, net | 20 | 2
Other Noncurrent Liabilities |  |
Offsetting Liabilities [Line Items] |  |
Gross amounts of recognized liabilities | 4 | 12
Gross asset amounts offset in the Balance Sheet | 0 | 0
Liability derivative contracts, net | $ 4 | $ 12

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