Commitments and Contingencies (Details 3) (EUR €) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 Claimant
Product Liability - Filters
Product Liability Litigation
Number of customers who obtained an order in the French Courts against SAS 3M Purification	1
Number of customers who filed a lawsuit against 3M Deutshland GmbH	1
Number of other customers the Company has resolved claims with	2
Product Liability Litigation - EDF
Product Liability Litigation
Number of lawsuits filed	1
Amount of potential damages (minimum) EDF incurred as stated by court appointed expert witness	100
Product Liability Litigation - EDF \| Maximum
Product Liability Litigation
Estimated time commercial court may take to render decision	1 year
Product Liability Litigation - EDF \| Minimum
Product Liability Litigation
Estimated time commercial court may take to render decision	6 months

Estimated time commercial court may take to render decision.

No definition available.

Name:	mmm_EstimatedDurationCommercialCourtMayTakeToRenderDecision
Namespace Prefix:	mmm_
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Balance Type:	na
Period Type:	duration

Represents the number of customers who filed a lawsuit against 3M Deutshland GmbH.

No definition available.

Name:	mmm_LossContingencyCustomersWhoFiledLawsuitAgainst3MDeutschlandGmbhNumber
Namespace Prefix:	mmm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the number of customers who obtained an order in the French Courts against SAS 3M Purification.

No definition available.

Name:	mmm_LossContingencyCustomersWhoObtainedOrderInFrenchCourtsAgainstSAS3MPurificationNumber
Namespace Prefix:	mmm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

The number of new lawsuits filed related to a loss contingency.

No definition available.

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

This is the potential impact (minimum) due to an expert witness appointed by the court to review possible product defects.

No definition available.

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

Number of claims settled.

No definition available.

Name:	us-gaap_LossContingencyClaimsSettledNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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

Name:	us-gaap_ProductOrServiceAxis=mmm_ProductLiabilityFiltersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_ProductOrServiceAxis=mmm_ProductLiabilityLitigationEDFMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: