Stock-Based Compensation (Details)		12 Months Ended	1 Months Ended
	Dec. 31, 2011 Participants	Dec. 31, 2011 Annual Y	May 31, 2010 3M 2008 Long-Term Incentive Plan	Dec. 31, 2011 3M 2008 Long-Term Incentive Plan	May 31, 2008 3M 2008 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award Activity
Expiration of annual grants (in years)		10
Retirement age eligibility for employees (in years)		55
Retirement eligibility for employees, minimum years of service required (in years)		5
Number of shares available for grant				22,004,273
Number of shares authorized			64,000,000		35,000,000
Additional number of shares authorized			29,000,000
Awards other than options and Stock Appreciation Rights, number of shares counted for every one share awarded under plan limit with grant dates prior to May 11, 2010 (in shares)				3.38
Awards other than options and Stock Appreciation Rights, number of shares counted for every one share awarded under plan limit with grant dates of May 11, 2010, or later (in shares)				2.87
Percent of stock-based compensation related to retiree-eligible population		28.00%
Vesting period, low end of range (in years)		1
Vesting period, high end of range (in years)		3
Number of participants with outstanding options, restricted stock, or restricted stock units	12,944