Pension and Other Postretirement Benefits (Details 4) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
The amounts recognized in the statement of financial position as of December 31 consist of:
Accrued expenses and liabilities held for sale	$ (14)	$ (21)
Pension
The amounts recognized in the statement of financial position as of December 31 consist of:
Net liability at December 31	(102)	(119)
The pre-tax amounts recognized in accumulated other comprehensive income consist of:
Net actuarial loss	638	568
Prior service cost	1	6
Net Loss, Prior service cost and Net transaction obligation, Total	639	574
Accumulated benefit obligation	2,361	2,273
Plans with accumulated benefit obligation in excess of plan assets as of December 31:
Projected benefit obligation	168	263
Accumulated benefit obligation	154	249
Fair value of plan assets	26	91
Other Postretirement Benefits
The amounts recognized in the statement of financial position as of December 31 consist of:
Net liability at December 31	(224)	(155)
The pre-tax amounts recognized in accumulated other comprehensive income consist of:
Net actuarial loss	(6)	(112)
Prior service cost	(1)	0
Net Loss, Prior service cost and Net transaction obligation, Total	(7)	(112)
Other Noncurrent Liabilities [Member] \| Pension
The amounts recognized in the statement of financial position as of December 31 consist of:
Other noncurrent liabilities	(257)	(213)
Other Noncurrent Liabilities [Member] \| Other Postretirement Benefits
The amounts recognized in the statement of financial position as of December 31 consist of:
Other noncurrent liabilities	(220)	(127)
Liabilities Held for Sale [Member] \| Pension
The amounts recognized in the statement of financial position as of December 31 consist of:
Accrued expenses and liabilities held for sale	0	(24)
Liabilities Held for Sale [Member] \| Other Postretirement Benefits
The amounts recognized in the statement of financial position as of December 31 consist of:
Accrued expenses and liabilities held for sale	0	(23)
Accrued Liabilities [Member] \| Pension
The amounts recognized in the statement of financial position as of December 31 consist of:
Accrued expenses and liabilities held for sale	(10)	(16)
Accrued Liabilities [Member] \| Other Postretirement Benefits
The amounts recognized in the statement of financial position as of December 31 consist of:
Accrued expenses and liabilities held for sale	(4)	(5)
Other Assets [Member] \| Pension
The amounts recognized in the statement of financial position as of December 31 consist of:
Other assets	165	134
Other Assets [Member] \| Other Postretirement Benefits
The amounts recognized in the statement of financial position as of December 31 consist of:
Other assets	$ 0	$ 0

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.

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-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

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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.

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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.

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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.

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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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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.

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

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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.

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