Pension and Other Postretirement Benefit Plans (Obligations and Funded Status at End of Year) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Funded status
Fair value of plan assets	$ 3,293	$ 3,682
United States Pension Benefits
Funded status
Fair value of plan assets	2,741	3,042	$ 2,835
Benefit obligations	3,470	3,796	3,546
Funded status	(729)	(754)
Amounts recognized in the consolidated balance sheet
Noncurrent asset	0	0
Current liability	(10)	(9)
Noncurrent liability	(719)	(745)
Amount recognized	(729)	(754)
Amounts recognized in accumulated other comprehensive loss (pre-tax)
Net actuarial loss	1,404	1,368
Prior service (credit) cost	(11)	(14)
Amount recognized	1,393	1,354
Foreign Pension Benefits
Funded status
Fair value of plan assets	552	640	206
Benefit obligations	865	1,026	439
Funded status	(313)	(386)
Amounts recognized in the consolidated balance sheet
Noncurrent asset	5	8
Current liability	(12)	(16)
Noncurrent liability	(306)	(378)
Amount recognized	(313)	(386)
Amounts recognized in accumulated other comprehensive loss (pre-tax)
Net actuarial loss	99	118
Prior service (credit) cost	(3)	0
Amount recognized	96	118
Other Postretirement Benefits
Funded status
Fair value of plan assets	0	0	0
Benefit obligations	441	502	$ 509
Funded status	(441)	(502)
Amounts recognized in the consolidated balance sheet
Noncurrent asset	0	0
Current liability	(51)	(56)
Noncurrent liability	(390)	(446)
Amount recognized	(441)	(502)
Amounts recognized in accumulated other comprehensive loss (pre-tax)
Net actuarial loss	20	53
Prior service (credit) cost	(25)	(120)
Amount recognized	$ (5)	$ (67)

The pretax 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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The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

+ References

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- Definition

The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan.

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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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- Definition

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.

+ References

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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

+ References

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- Definition

This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

+ References

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