Benefit Plans (Net Funded Status) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
U.S. Defined Benefit Plans
CHANGE IN PROJECTED BENEFIT OBLIGATION:
Benefit obligation, beginning period	$ 1,059	$ 1,210
Service cost	14	16	14
Interest cost	50	46	48
Employee contributions	0	0
Plan amendments	8	0
Benefits paid	(59)	(75)
Actuarial (gain) loss	163	(138)
Effect of foreign currency exchange rate changes	0	0
Benefit obligation, ending period	1,235	1,059	1,210
CHANGE IN PLAN ASSETS:
Fair value of plan assets, beginning period	941	883
Actual return on plan assets	123	81
Employer contributions	56	52
Employee contributions	0	0
Benefits paid	(59)	(75)
Effect of foreign currency exchange rate changes	0	0
Fair value of plan assets, ending period	1,061	941	883
Funded status as of December 31	(174)	(118)
Foreign Defined Benefit Plans
CHANGE IN PROJECTED BENEFIT OBLIGATION:
Benefit obligation, beginning period	4,749	6,768
Service cost	16	26	18
Interest cost	489	515	509
Employee contributions	4	4
Plan amendments	(3)	0
Benefits paid	(415)	(407)
Actuarial (gain) loss	87	(1,436)
Effect of foreign currency exchange rate changes	(564)	(721)
Benefit obligation, ending period	4,363	4,749	6,768
CHANGE IN PLAN ASSETS:
Fair value of plan assets, beginning period	3,605	4,712
Actual return on plan assets	360	(345)
Employer contributions	135	160
Employee contributions	4	4
Benefits paid	(415)	(407)
Effect of foreign currency exchange rate changes	(417)	(519)
Fair value of plan assets, ending period	3,272	3,605	4,712
Funded status as of December 31	$ (1,091)	$ (1,144)

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.

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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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.

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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.

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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.

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

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The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

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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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Amount of gain (loss) from foreign currency exchange rate changes for benefit obligation for plans of a foreign operation whose functional currency is not the reporting currency.

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The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

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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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The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

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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.

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