Consolidated Statement of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net sales	$ 7,486	$ 7,311
Operating expenses
Cost of sales	3,889	3,802
Selling, general and administrative expenses	1,552	1,533
Research, development and related expenses	411	398
Total operating expenses	5,852	5,733
Operating income	1,634	1,578
Interest expense and income
Interest expense	40	43
Interest income	(9)	(10)
Total interest expense - net	31	33
Income before income taxes	1,603	1,545
Provision for income taxes	462	442
Net income including noncontrolling interest	1,141	1,103
Less: Net income attributable to noncontrolling interest	16	22
Net income attributable to 3M	$ 1,125	$ 1,081
Weighted average 3M common shares outstanding - basic (in shares)	696.8	711.5
Earnings per share attributable to 3M common shareholders - basic (in dollars per share)	$ 1.61	$ 1.52
Weighted average 3M common shares outstanding - diluted (in shares)	706.1	726.4
Earnings per share attributable to 3M common shareholders - diluted (in dollars per share)	$ 1.59	$ 1.49
Cash dividends paid per 3M common share (in dollars per share)	$ 0.59	$ 0.55