Supplemental Cash Flow Information (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplemental Cash Flow Elements
Cash income tax payments, net of refunds	$ 1,968us-gaap_IncomeTaxesPaidNet	$ 1,803us-gaap_IncomeTaxesPaidNet	$ 1,717us-gaap_IncomeTaxesPaidNet
Cash interest payments	178us-gaap_InterestPaid	169us-gaap_InterestPaid	166us-gaap_InterestPaid
Capitalized interest	$ 15us-gaap_InterestPaidCapitalized	$ 21us-gaap_InterestPaidCapitalized	$ 23us-gaap_InterestPaidCapitalized

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.

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- Definition

The amount of cash paid for interest during the period.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

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- Definition

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

+ References

+ Details

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- Details

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