The number of participants with outstanding options, restricted stock, or restricted stock units.

No definition available.

Name:	mmm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOptionsRestrictedStockAndRestrictedStockUnitsNumberOfParticipants
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- Definition

Shareholders approve the number of shares to be awarded under 3Ms Long Term Incentive Plan. Awards denominated in shares count against the approved share limit as a certain number of shares for every one share covered by such award, which varies depending on the grant date of the award. This element covers shares awarded with grant dates prior to May 11, 2010.

+ References

No definition available.

+ Details

Name:	mmm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAndStockAppreciationRightsNumberOfSharesCountedAgainstApprovedShareLimitForEveryOneShareCoveredByAward1
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- Definition

+ References

No definition available.

+ Details

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- Definition

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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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- 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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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
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- Details

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Stock-Based Compensation (Details)	12 Months Ended
Stock-Based Compensation (Details)	Dec. 31, 2014 Participants	Dec. 31, 2013	Dec. 31, 2012	May 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award Activity
Number of participants with outstanding options, restricted stock, or restricted stock units	9,525
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)	33.00%
General Employees' Stock Purchase Plan (GESPP)
Share-based Compensation Arrangement by Share-based Payment Award Activity
Number of shares authorized	60,000,000
Number of shares available for grant under the 2008 Long Term Incentive Plan Program (including additional subsequent shareholder approvals)	29,112,004	30,185,960	31,445,207
3M Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award Activity
Number of shares authorized				100,000,000
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	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 on or after May 11, 2010 and prior to May 8, 2012	2.87
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 8, 2012, or later	3.50
Number of shares available for grant under the 2008 Long Term Incentive Plan Program (including additional subsequent shareholder approvals)	28,293,674