Name:	mmm_DecreaseInProjectedPensionObligationLiabilityDueToRetireeWelfareBenefitPlanRemeasurement
Namespace Prefix:	mmm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The employer's best estimate, as soon as it can be reasonably determined, of estimated pension and postretirement contributions to be paid to the plan during the current fiscal year.

No definition available.

Name:	mmm_EstimatedEmployerPensionAndPostretirementContributionsInCurrentFiscalYear
Namespace Prefix:	mmm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The percentage of company contribution to eligible 3M Japan employee's defined contribution plan effective July 2015 after March 2015 Japan Limited Definted Benefit Corporate Pension Plan modification.

No definition available.

Name:	mmm_JapanLimitedDefinedBenefitCorporatePensionPlanCompanyProvidedContributionMatchPercentage
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
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 original percentage that the Company would credit the Retiree Medical Saving Account and the Medicare Health Reimbursement Arrangement as an inflation indexation.

No definition available.

Name:	mmm_OriginalPercentageMedicalInflationIndexationByCompanyInYear
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The revised percentage that the Company would credit the Retiree Medical Saving Account and the Medicare Health Reimbursement Arrangement as an inflation indexation.

No definition available.

Name:	mmm_Revisedpercentagemedicalinflationindexationbycompanyinyear
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
Balance Type:	na
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=58740216&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanContributionsByEmployer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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.

No definition available.

Name:	us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of net gain (loss) recognized in net periodic benefit cost due to settlements and curtailments. Curtailments result from an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services. Settlements result from an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(7)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlementsAndCurtailments1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Number of defendants named in a legal action.

No definition available.