Supplemental Equity and Comprehensive Income Information - Dividends (Details) - USD ($) $ / shares in Units, $ in Billions	3 Months Ended	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2014
Supplemental Equity and Comprehensive Income Information
Dividends that have been declared but paid in subsequent period (in dollars per share)			$ 1.025
Cash dividends paid per 3M common share (in dollars per share)	$ 1.11	$ 1.025
Dividends Payable Current			$ 0.6

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Current Liabilities
-URI http://asc.fasb.org/extlink&oid=6509677

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant