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The percentage of the total value of investments that are held with WG Trading company, maximum.

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The total amount of net periodic benefit cost for defined benefit plans for the period, not including the costs for settlements, curtailments, special termination benefits and other.

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

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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.

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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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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.

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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	6 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
	Jun. 30, 2011	Mar. 31, 2011 LimitedPartners	Jun. 30, 2011 Qualified and Non-qualified Pension Benefits	Jun. 30, 2010 Qualified and Non-qualified Pension Benefits	Jun. 30, 2011 United States Qualified and Non-qualified Pension Benefits	Jun. 30, 2010 United States Qualified and Non-qualified Pension Benefits	Jun. 30, 2011 United States Qualified and Non-qualified Pension Benefits	Jun. 30, 2010 United States Qualified and Non-qualified Pension Benefits	Jun. 30, 2011 International Qualified and Non-qualified Pension Benefits	Jun. 30, 2010 International Qualified and Non-qualified Pension Benefits	Jun. 30, 2011 International Qualified and Non-qualified Pension Benefits	Jun. 30, 2010 International Qualified and Non-qualified Pension Benefits	Jun. 30, 2011 Postretirement Benefits	Jun. 30, 2010 Postretirement Benefits	Jun. 30, 2011 Postretirement Benefits	Jun. 30, 2010 Postretirement Benefits
Net periodic benefit cost (benefit)
Service cost					$ 52	$ 51	$ 103	$ 101	$ 28	$ 27	$ 56	$ 55	$ 15	$ 14	$ 30	$ 28
Interest cost					155	159	313	319	62	63	124	125	23	22	46	44
Expected return on plan assets					(232)	(232)	(464)	(464)	(69)	(72)	(139)	(143)	(20)	(21)	(39)	(42)
Amortization of transition (asset) obligation										1		1
Amortization of prior service cost (benefit)					3	3	6	6	(4)	(1)	(7)	(2)	(18)	(24)	(36)	(47)
Amortization of net actuarial (gain) loss					84	55	167	110	28	22	56	43	26	22	52	43
Net periodic benefit cost (benefit)					62	36	125	72	45	40	90	79	26	13	53	26
Settlements, curtailments, special termination benefits and other										(22)		(22)
Net periodic benefit cost (benefit) after settlements, curtailments, special termination benefits and other					62	36	125	72	45	18	90	57	26	13	53	26
Contributions made to the Company's plans			77												48
Expected future employer contributions in next fiscal year, low end of range			400
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%