Employee Retirement Benefits (Benefit Obligation Activity Using An Actuarial Measurement Date For Qualified Plan And SERP) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Change in projected benefit obligation:
Benefit obligation, January 1	$ 284	$ 320
Service cost	10us-gaap_DefinedBenefitPlanServiceCost	13us-gaap_DefinedBenefitPlanServiceCost	12us-gaap_DefinedBenefitPlanServiceCost
Interest cost	15us-gaap_DefinedBenefitPlanInterestCost	13us-gaap_DefinedBenefitPlanInterestCost	14us-gaap_DefinedBenefitPlanInterestCost
Actuarial loss (gain)	35	(34)
Benefits paid	(27)us-gaap_DefinedBenefitPlanBenefitsPaid	(28)us-gaap_DefinedBenefitPlanBenefitsPaid
Other	2us-gaap_DefinedBenefitPlanOtherCosts	0us-gaap_DefinedBenefitPlanOtherCosts	0us-gaap_DefinedBenefitPlanOtherCosts
Projected benefit obligation, December 31	319	284	320
Accumulated benefit obligation	284	257
Change in plan assets:
Fair value of plan assets, January 1	280	238
Actual return on plan assets	30	55
Employer contribution	5	15
Benefits paid	(27)us-gaap_DefinedBenefitPlanBenefitsPaid	(28)us-gaap_DefinedBenefitPlanBenefitsPaid
Fair value of plan assets, December 31	288	280	238
Unfunded status:
Funded status, December 31	$ (31)	$ (4)

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

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- Definition

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)

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- Definition

Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

+ References

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

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

+ References

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-Name Accounting Standards Codification

-Glossary Postretirement Benefits

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The increase in the fair value of plan assets from contributions made by the employer.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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Amount of other defined benefit plan costs.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

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-Name Accounting Standards Codification

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