Quarterly Data (Unaudited) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Quarterly Data (Unaudited)
Net sales	$ 7,578us-gaap_SalesRevenueNet	$ 7,831us-gaap_SalesRevenueNet
Cost of sales	3,821us-gaap_CostOfRevenue	4,031us-gaap_CostOfRevenue
Net income including noncontrolling interest	1,201us-gaap_ProfitLoss	1,225us-gaap_ProfitLoss
Net income attributable to 3M	$ 1,199us-gaap_NetIncomeLoss	$ 1,207us-gaap_NetIncomeLoss
Earnings per share attributable to 3M common shareholders - basic (in dollars per share)	$ 1.88us-gaap_EarningsPerShareBasic	$ 1.83us-gaap_EarningsPerShareBasic
Earnings per share attributable to 3M common shareholders - diluted (in dollars per share)	$ 1.85us-gaap_EarningsPerShareDiluted	$ 1.79us-gaap_EarningsPerShareDiluted

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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