Stock-Based Compensation (Details) - shares	6 Months Ended
Jun. 30, 2015	May. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award Activity
Retirement age eligibility for employees	55 years
Retirement eligibility for employees, minimum years of service required	5 years
Percent of stock-based compensation related to retiree-eligible population (as a percent)	35.00%
3M Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award Activity
Number of shares authorized		100,000,000
Number of shares available for grant under the 2008 Long Term Incentive Plan Program (including additional subsequent shareholder approvals)	19,824,070

Percent of stock-based compensation related to retiree-eligible population.

No definition available.

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- Definition

The age at which employees of the entity are eligible for retirement, which combined with reaching years of service triggers expense recognition of share based compensation expense, in years.

+ References

No definition available.

+ Details

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- Definition

The number of years of service which combined with reaching eligible retirement age triggers expense recognition of share based compensation expense, in years.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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