Supplemental Equity and Comprehensive Income Information (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Supplemental Equity and Comprehensive Income Information
Net income attributable to 3M	$ 1,199us-gaap_NetIncomeLoss	$ 1,207us-gaap_NetIncomeLoss

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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

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

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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