Consolidated Statement of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net sales	$ 7,686	$ 8,134	$ 15,264	$ 15,965
Operating expenses
Cost of sales	3,858	4,184	7,679	8,215
Selling, general and administrative expenses	1,550	1,646	3,114	3,278
Research, development and related expenses	438	448	901	900
Total operating expenses	5,846	6,278	11,694	12,393
Operating income	1,840	1,856	3,570	3,572
Interest expense and income
Interest expense	35	45	66	82
Interest income	(7)	(9)	(11)	(18)
Total interest expense - net	28	36	55	64
Income before income taxes	1,812	1,820	3,515	3,508
Provision for income taxes	509	537	1,011	1,000
Net income including noncontrolling interest	1,303	1,283	2,504	2,508
Less: Net income attributable to noncontrolling interest	3	16	5	34
Net income attributable to 3M	$ 1,300	$ 1,267	$ 2,499	$ 2,474
Weighted average 3M common shares outstanding - basic (in shares)	631.3	652.0	633.8	656.7
Earnings per share attributable to 3M common shareholders - basic (in dollars per share)	$ 2.06	$ 1.94	$ 3.94	$ 3.77
Weighted average 3M common shares outstanding - diluted (in shares)	643.0	664.6	646.1	669.6
Earnings per share attributable to 3M common shareholders - diluted (in dollars per share)	$ 2.02	$ 1.91	$ 3.87	$ 3.70
Cash dividends paid per 3M common share (in dollars per share)	$ 1.025	$ 0.855	$ 2.05	$ 1.71