Consolidated Statement of Income (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net sales	$ 29,611	$ 26,662	$ 23,123
Operating expenses
Cost of sales	15,693	13,831	12,109
Selling, general and administrative expenses	6,170	5,479	4,907
Research, development and related expenses	1,570	1,434	1,293
Total operating expenses	23,433	20,744	18,309
Operating income	6,178	5,918	4,814
Interest expense and income
Interest expense	186	201	219
Interest income	(39)	(38)	(37)
Total interest expense - net	147	163	182
Income before income taxes	6,031	5,755	4,632
Provision for income taxes	1,674	1,592	1,388
Net income including noncontrolling interest	4,357	4,163	3,244
Less: Net income attributable to noncontrolling interest	74	78	51
Net income attributable to 3M	$ 4,283	$ 4,085	$ 3,193
Weighted average 3M common shares outstanding - basic (in shares)	708.5	713.7	700.5
Earnings per share attributable to 3M common shareholders - basic (in dollars per share)	$ 6.05	$ 5.72	$ 4.56
Weighted average 3M common shares outstanding - diluted (in shares)	719.0	725.5	706.7
Earnings per share attributable to 3M common shareholders - diluted (in dollars per share)	$ 5.96	$ 5.63	$ 4.52
Cash dividends paid per 3M common share (in dollars per share)	$ 2.20	$ 2.10	$ 2.04