Retirement Plans Retirement Plans (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
General Discussion of Pension and Other Postretirement Benefits [Abstract]
Estimated net actuarial loss for the defined benefit pension plans to be recognized from accumulated other comprehensive gain (loss)	$ 9
Pesnion plans with an accumulated benefit obligation in excess of plan assets - projected benefit obligations	570	456
Pension plans with an accumulated benefit obligation in excess of plan assets - accumulated benefit obligations	533	427
Pesnion plans with an accumulated benefit obligation in excess of plan assets - fair value of plan assets	0	281
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	$ 19

The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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If aggregate disclosures are presented, the aggregate projected benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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