Retirement-Related Benefits (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Retirement-related plans cost
Total net periodic pension (income)/cost of defined benefit plans	$ (25)	$ (394)	$ (384)
Defined Benefit Pension Plans
Retirement-related plans cost
Total net periodic pension (income)/cost of defined benefit plans	(40)	(408)	(398)
Defined Benefit Pension Plans \| U.S. Plan(s)
Retirement-related plans cost
Interest cost	2,456	2,601	2,682
Expected return on plan assets	(4,043)	(4,017)	(4,009)
Amortization of prior service costs/(credits)	10	10	10
Recognized actuarial losses	818	471	411
Curtailments and settlements		1
Total net periodic pension (income)/cost of defined benefit plans	(759)	(935)	(906)
Defined Benefit Pension Plans \| Non-U.S. Plans
Retirement-related plans cost
Service cost	505	508	585
Interest cost	1,843	1,841	1,898
Expected return on plan assets	(2,521)	(2,461)	(2,534)
Amortization of transition assets	0	0	0
Amortization of prior service costs/(credits)	(162)	(174)	(126)
Recognized actuarial losses	957	712	624
Curtailments and settlements	1	27	(126)
Multi-employer plan/other costs	111	89	200
Total net periodic pension (income)/cost of defined benefit plans	734	541	521
Nonpension Postretirement Plans
Retirement-related plans cost
Total net periodic pension (income)/cost of defined benefit plans	345	347	350
Nonpension Postretirement Plans \| U.S. Plan(s)
Retirement-related plans cost
Service cost	33	33	41
Interest cost	236	262	289
Amortization of prior service costs/(credits)		(14)	(39)
Total net periodic pension (income)/cost of defined benefit plans	269	281	292
Nonpension Postretirement Plans \| Non-U.S. Plans
Retirement-related plans cost
Service cost	11	9	10
Interest cost	67	59	51
Expected return on plan assets	(10)	(9)	(8)
Amortization of transition assets	0	0	0
Amortization of prior service costs/(credits)	(4)	(5)	(6)
Recognized actuarial losses	13	12	11
Total net periodic pension (income)/cost of defined benefit plans	$ 76	$ 66	$ 58

The amount of multiemployer plans and other costs during the period.

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The amount of gains or losses recognized in net periodic benefit cost.

+ References

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

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The amount of the transition obligation or asset recognized in net periodic benefit cost.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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- Definition

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 total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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-Paragraph 5

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The aggregate amount of net gain (loss) recognized in net periodic benefit cost due to settlements and curtailments. Curtailments result from an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services. Settlements result from an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts to cover vested benefits.

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- Definition

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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