Retirement Plans (Amounts Deferred In AOCI) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Pension Benefits
Compensation And Retirement Disclosure Line Items
Net actuarial loss	$ 5,737	$ 4,790
Prior service (credit) cost	(214)	(258)
Total amount recognized in AOCI, pre-tax	5,523	4,532
Other Postretirement Benefit Plans, Defined Benefit
Compensation And Retirement Disclosure Line Items
Net actuarial loss	401	234
Prior service (credit) cost	21	30
Total amount recognized in AOCI, pre-tax	$ 422	$ 264

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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- 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.

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

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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+ Details