Consolidated Statement of Income - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Consolidated Statement of Income
Net sales	$ 32,765	$ 31,657	$ 30,109
Operating expenses
Cost of sales	16,682	16,055	15,118
Selling, general and administrative expenses	7,602	6,626	6,311
Research, development and related expenses	1,821	1,870	1,764
Gain on sale of businesses	(547)	(586)	(111)
Total operating expenses	25,558	23,965	23,082
Operating income	7,207	7,692	7,027
Interest expense and income
Other expense (income), net	207	144	(26)
Income before income taxes	7,000	7,548	7,053
Provision for income taxes	1,637	2,679	1,995
Net income including noncontrolling interest	5,363	4,869	5,058
Less: Net income attributable to noncontrolling interest	14	11	8
Net income attributable to 3M	$ 5,349	$ 4,858	$ 5,050
Weighted average 3M common shares outstanding - basic (in shares)	588.5	597.5	604.7
Earnings per share attributable to 3M common shareholders - basic (in dollars per share)	$ 9.09	$ 8.13	$ 8.35
Weighted average 3M common shares outstanding - diluted (in shares)	602.0	612.7	618.7
Earnings per share attributable to 3M common shareholders - diluted (in dollars per share)	$ 8.89	$ 7.93	$ 8.16