Name:	mmm_DefinedBenefitPlanSpecialTerminationBenefitsNumberOfAdditionalYearsOfAgeOfPensionServiceForCertainBenefitCalculations
Namespace Prefix:	mmm_
Data Type:	xbrli:durationItemType
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The number of additional years of pension service for enhanced pension benefits that are offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time.

No definition available.

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Namespace Prefix:	mmm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The number of participants who will receive special termination benefits that are offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time.

No definition available.

Name:	mmm_DefinedBenefitPlanSpecialTerminationBenefitsNumberOfParticipants
Namespace Prefix:	mmm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

The percentage of WG Trading Company holdings in relation to total fair value of the company's total plan assets (maximum).

No definition available.

Name:	mmm_LimitedPartnershipInterestsWithWGTradingCompanyMaximum
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The number of additional limited partners of WG Trading Company, in addition to 3M, who objected and appealed the court's order to the United States Court of Appeals for the Second Circuit.

No definition available.

Name:	mmm_NumberOfAdditionalLimitedPartnersOfWGTradingCompanyInAdditionTo3MWhoObjectedAndAppealedCourtsOrderToUnitedStatesCourtOfAppealsForSecondCircuit
Namespace Prefix:	mmm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The income statement impact from pension expense related to the former U.S. employee 2014 lump sum payout offer.

No definition available.

Name:	mmm_PensionExpenseRelatedToProjectedBenefitObligationIn2014LumpSumPayout
Namespace Prefix:	mmm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The pension benefit obligation (PBO) term vested liability reduction from former US employee lump sum payout offer as a percent of the overall U.S. pension PBO liability based on December 31, 2013 valuation.

No definition available.

Name:	mmm_ProjectedBenefitObligationTermVestedLiabilityReductionAsPercentOfOverallUSPension
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The pension benefit obligation (PBO) term vested liability reduction from former US employee lump sum payout offer as a percent of the term vested eligible PBO based on December31, 2013 valuation.

No definition available.

Name:	mmm_ProjectedBenefitObligationTermVestedLiabilityReductionAsPercentOfTermVestedEligible
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The estimated reduction of the term vested liability amount of projected benefit obligation (PBO) due to offering term vested former US employees a lump sum payout of their pension benefits.

No definition available.

Name:	mmm_ProjectedBenefitObligationTermVestedLiabilityReductionDueToTermVestedFormerEmployeesOfferingOfLumpSumPayout
Namespace Prefix:	mmm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The increase in the fair value of plan assets from contributions made by the employer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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If applicable, the cost of providing special or contractual termination benefits recognized during the period on the projected benefit obligation.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (q)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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