Supplemental Equity and Comprehensive Income Information - AOCI rf (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
AOCI Attributable to 3M, Net of Tax [Roll Forward]
Stockholders' Equity Attributable to 3M, Beginning Balance	$ 10,298
Other comprehensive income (loss), before tax:
Stockholders' Equity Attributable to 3M, Ending Balance	10,989
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to 3M, Net of Tax [Roll Forward]
Stockholders' Equity Attributable to 3M, Beginning Balance	(7,245)	$ (6,359)
Other comprehensive income (loss), before tax:
Amounts before reclassifications	125	(61)
Amounts reclassified out	101	51
Total other comprehensive income (loss), before tax	226	(10)
Tax effect	70	108
Total other comprehensive income (loss), net of tax	296	98
Stockholders' Equity Attributable to 3M, Ending Balance	(6,949)	(6,261)
Cumulative Translation Adjustment
AOCI Attributable to 3M, Net of Tax [Roll Forward]
Stockholders' Equity Attributable to 3M, Beginning Balance	(2,008)	(1,679)
Other comprehensive income (loss), before tax:
Amounts before reclassifications	226	60
Total other comprehensive income (loss), before tax	226	60
Tax effect	63	79
Total other comprehensive income (loss), net of tax	289	139
Stockholders' Equity Attributable to 3M, Ending Balance	(1,719)	(1,540)
Gains (losses) associated with defined benefit pension and postretirement plans amortization
AOCI Attributable to 3M, Net of Tax [Roll Forward]
Stockholders' Equity Attributable to 3M, Beginning Balance	(5,328)	(4,804)
Other comprehensive income (loss), before tax:
Amounts reclassified out	119	103
Total other comprehensive income (loss), before tax	119	103
Tax effect	(36)	(34)
Total other comprehensive income (loss), net of tax	83	69
Stockholders' Equity Attributable to 3M, Ending Balance	(5,245)	(4,735)
Cash flow hedging instruments gains (losses)
AOCI Attributable to 3M, Net of Tax [Roll Forward]
Stockholders' Equity Attributable to 3M, Beginning Balance	91	124
Other comprehensive income (loss), before tax:
Amounts before reclassifications	(101)	(121)
Amounts reclassified out	(18)	(52)
Total other comprehensive income (loss), before tax	(119)	(173)
Tax effect	43	63
Total other comprehensive income (loss), net of tax	(76)	(110)
Stockholders' Equity Attributable to 3M, Ending Balance	$ 15	$ 14