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The number of additional limited partners of WG Trading Company, in addition to 3M, who objected and appealed the court's order to the United States Court of Appeals for the Second Circuit.

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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 net gain (loss) recognized in net periodic benefit cost as a result of 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.

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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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The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

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Pension and Postretirement Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended		3 Months Ended	9 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2011	Mar. 31, 2011 LimitedPartner	Jun. 30, 2010 Qualified and Non-qualified Pension Benefits	Sep. 30, 2011 Qualified and Non-qualified Pension Benefits	Sep. 30, 2011 United States Qualified and Non-qualified Pension Benefits	Sep. 30, 2010 United States Qualified and Non-qualified Pension Benefits	Sep. 30, 2011 United States Qualified and Non-qualified Pension Benefits	Sep. 30, 2010 United States Qualified and Non-qualified Pension Benefits	Sep. 30, 2011 International Qualified and Non-qualified Pension Benefits	Sep. 30, 2010 International Qualified and Non-qualified Pension Benefits	Sep. 30, 2011 International Qualified and Non-qualified Pension Benefits	Sep. 30, 2010 International Qualified and Non-qualified Pension Benefits	Sep. 30, 2011 Postretirement Benefits	Sep. 30, 2010 Postretirement Benefits	Sep. 30, 2011 Postretirement Benefits	Sep. 30, 2010 Postretirement Benefits
Net periodic benefit cost (benefit)
Service cost					$ 51	$ 50	$ 154	$ 151	$ 27	$ 28	$ 83	$ 83	$ 16	$ 13	$ 46	$ 41
Interest cost					157	160	470	479	62	62	186	187	23	22	69	66
Expected return on plan assets					(231)	(233)	(695)	(697)	(70)	(71)	(209)	(214)	(20)	(20)	(59)	(62)
Amortization of transition (asset) obligation												1
Amortization of prior service cost (benefit)					2	4	8	10	(3)	(1)	(10)	(3)	(18)	(23)	(54)	(70)
Amortization of net actuarial (gain) loss					83	55	250	165	28	21	84	64	25	21	77	64
Net periodic benefit cost (benefit)					62	36	187	108	44	39	134	118	26	13	79	39
Settlements, curtailments, special termination benefits and other												(22)
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other					62	36	187	108	44	39	134	96	26	13	79	39
Contributions made to the Company's plans				310											63
Expected future employer contributions in next fiscal year, low end of range				500
Expected future employer contributions in next fiscal year, high end of range				600
Curtailment gain			$ 22
Number of additional limited partners of WG Trading Company, in addition to 3M, who objected and appealed the court's order to the United States Court of Appeals for the Second Circuit		6
Percentage of the entity's total fair value investments held with WG Trading Company, maximum (as a percent)	1.00%