Derivatives (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011 Y Acquistion CounterParties Segment	Dec. 31, 2010
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	$ 114	$ 114	$ 77
Fair Value of Derivative Instruments, Liabilities	46	46	87
Year-on-year currency effects, including hedging impact	51	131
Year-on-year derivative and other transaction gains and (losses) impact	18	(8)
Primary derivative counterparties		2
Foreign currency forward/option contracts \| Derivatives designated as hedging instruments \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	65	65	26
Foreign currency forward/option contracts \| Derivatives designated as hedging instruments \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	31	31	48
Commodity price swap contracts \| Derivatives designated as hedging instruments \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	4	4	5
Interest rate swap contracts \| Derivatives designated as hedging instruments \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	31	31	39
Derivatives designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	96	96	65
Fair Value of Derivative Instruments, Liabilities	35	35	53
Foreign currency forward/option contracts \| Derivatives not designated as hedging instruments \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	18	18	12
Foreign currency forward/option contracts \| Derivatives not designated as hedging instruments \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	11	11	34
Derivatives not designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	18	18	12
Fair Value of Derivative Instruments, Liabilities	$ 11	$ 11	$ 34

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

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- Definition

The year-on-year currency effects, including hedging impacts, on 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.

+ Details

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- Definition

The year-on-year derivative and other transaction gains and losses impact on net income attributable to the parent.

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- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ 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)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624163-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

+ Details

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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