Derivatives (Details 4) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($)	Jun. 30, 2015 USD ($) CounterParties	Dec. 31, 2014 USD ($)
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	$ 365	$ 365	$ 256
Fair Value of Derivative Instruments, Liabilities	81	81	43
Year-on-year currency effects impact on pre-tax net income, including hedging impact	(110)	(200)
Year-on-year derivative and other transaction gains and (losses) pre-tax impact	40	$ 80
Number of primary derivative counterparties \| CounterParties		1
Number of master netting agreements supported by primary counterparty's parent guarantee \| CounterParties		16
Number of credit support agreements by primary counterparty \| CounterParties		15
Derivatives designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	272	$ 272	190
Fair Value of Derivative Instruments, Liabilities	7	7	10
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	179	179	116
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	73	73	47
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	4	4	2
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	3	3	1
Derivatives designated as hedging instruments \| Commodity price swap contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets			0
Derivatives designated as hedging instruments \| Commodity price swap contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities			4
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	20	20	27
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	0	0	3
Derivatives not designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	93	93	66
Fair Value of Derivative Instruments, Liabilities	74	74	33
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	92	92	66
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	1	1
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	71	71	$ 33
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	1	1
Derivatives not designated as hedging instruments \| Commodity price swap contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	0	0
Derivatives not designated as hedging instruments \| Commodity price swap contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	$ 2	$ 2

Number of primary derivatives counterparties that 3M has credit support agreements with primary counterparties parent.

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Number of primary derivatives counterparties that 3M has master netting agreement with that is supported by primary counterparties parent guarantee.

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Number of primary derivatives counterparties that 3M has credit support agreements in place with.

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The year-on-year currency effects, including hedging impacts, on pre-tax net income attributable to 3M. This estimate includes the effect of translating profits from local currencies into U.S. dollars; the impact of currency fluctuations on the transfer of goods between 3M operations in the United States and abroad; and transaction gains and losses, including derivative instruments designed to reduce foreign currency exchange rate risks.

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 210

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-Section 50

-Paragraph 3

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-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313

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