Supplemental Equity and Comprehensive Income Information - Reclassifications Out of AOCI (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Amount Reclassified from Accumulated Other Comprehensive Income
Other expense (income), net	$ (24)	$ (31)	$ (112)	$ (113)
Total before tax	4,132	1,757	5,795	5,640
Tax effect	271	324	550	1,058
Net income	3,863	1,437	5,248	4,589
Cost of sales	4,728	4,853	14,647	14,097
Net income attributable to 3M	3,859	1,434	5,236	4,582
Reclassification out of Accumulated Other Comprehensive Income
Amount Reclassified from Accumulated Other Comprehensive Income
Net income attributable to 3M	(63)	(133)	(218)	(389)
Defined benefit pension and postretirement plans adjustments | Reclassification out of Accumulated Other Comprehensive Income
Amount Reclassified from Accumulated Other Comprehensive Income
Total before tax	(112)	(158)	(339)	(477)
Tax effect	26	39	81	118
Net income	(86)	(119)	(258)	(359)
Transition asset | Reclassification out of Accumulated Other Comprehensive Income
Amount Reclassified from Accumulated Other Comprehensive Income
Other expense (income), net	0	(1)	(1)	(2)
Prior service benefit | Reclassification out of Accumulated Other Comprehensive Income
Amount Reclassified from Accumulated Other Comprehensive Income
Other expense (income), net	14	15	42	45
Net actuarial loss | Reclassification out of Accumulated Other Comprehensive Income
Amount Reclassified from Accumulated Other Comprehensive Income
Other expense (income), net	(126)	(172)	(378)	(518)
Curtailments/Settlements | Reclassification out of Accumulated Other Comprehensive Income
Amount Reclassified from Accumulated Other Comprehensive Income
Other expense (income), net	0	0	(2)	(2)
Cash flow hedging instruments gains (losses) | Reclassification out of Accumulated Other Comprehensive Income
Amount Reclassified from Accumulated Other Comprehensive Income
Other expense (income), net	(3)	(3)	(7)	(7)
Total before tax	30	(18)	52	(39)
Tax effect	(7)	4	(12)	9
Net income	23	(14)	40	(30)
Cost of sales	$ 33	$ (15)	$ 59	$ (32)