Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Decrease (increase) in current assets:
Receivables, net	$ 817	$ (47)
Inventories	(291)	147
Income taxes receivable	41	45
Prepaid expenses and other	12	(126)
Increase (decrease) in current liabilities:
Accounts payable	(306)	108
Accrued expenses	20	(137)
Taxes other than income taxes	(123)	(113)
Income taxes payable	(19)	(54)
Changes in current assets and current liabilities	151	(177)
Cash Flows Related to Interest and Income Taxes
Interest paid in excess of amount capitalized	128	95
Income taxes paid, net	$ 96	$ 95

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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The increase (decrease) during the period in the amount due for taxes based on the reporting entity's earnings or attributable to the entity's income earning process (business presence) within a given jurisdiction.

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The increase (decrease) during the reporting period in income taxes receivable, which represents the amount due from tax authorities for refunds of overpayments or recoveries of income taxes paid.

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Amount of increase (decrease) in current operating assets after deduction of current operating liabilities classified as other.

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Amount of increase (decrease) in prepaid expenses, and assets classified as other.

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The increase (decrease) during the period in the amount of cash payments due to taxing authorities for non-income-related taxes.

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The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities.

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The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

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Cash Flows Related to Interest and Income Taxes [Abstract]

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