Noncurrent Other Liabilities (Schedule of Noncurrent Other Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Other Liabilities, Noncurrent [Abstract]
Asset retirement obligations	$ 13	$ 7
Deferred proceeds	44	47
Deferred revenue	7	6
Derivatives (Note 22)	11	0
Environmental (Note 16)	49	59
Income taxes payable (Note 19)	0	197
Insurance	37	43
Other	47	54
Total	$ 208	$ 413

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due beyond one year or the operating cycle, whichever is longer. Alternate captions include income taxes payable, noncurrent.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Estimated costs as of the balance sheet date of settling insured claims and costs incurred in the claims settlement process for claims that have not yet been submitted to the insurance company for reimbursement.

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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