Business Segment Information Business Segment Information (Restructuring Costs) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 20us-gaap_RestructuringCharges	$ 110us-gaap_RestructuringCharges
Paid in cash	53us-gaap_PaymentsForRestructuring	25us-gaap_PaymentsForRestructuring
Non-cash portion	0	46
Remaining accrual	6us-gaap_RestructuringReserve
Implementation Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	9	19
Paid in cash	9	19
Non-cash portion	0	0
Remaining accrual	0
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	11	45
Paid in cash	44	6
Non-cash portion	0	0
Remaining accrual	6
Benefits Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	0	26
Paid in cash	0	0
Non-cash portion	0	26
Remaining accrual	0
Property, Plant, and Equipment Impairments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	0	20
Paid in cash	0	0
Non-cash portion	0	20
Remaining accrual	$ 0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ 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 (b)

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-Name Accounting Standards Codification

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

+ Details

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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+ Details

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- Definition

Amount of consideration other than cash used to fully or partially settle an accrued restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

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-Subsection 3, 4

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-Topic 420

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-Section S99

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-Subparagraph (SAB TOPIC 5.P.4(b)(2))

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+ Details

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