Acquisitions and Divestitures - Acquisitions (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Business Acquisitions Information
Purchase price paid for business combinations (net of cash acquired)		$ 4
Supplemental information:
Purchase price paid for business combinations (net of cash acquired)		$ 4
Scott Safety
Supplemental information:
Estimated purchase price to acquire business	$ 2,000
Annual sales prior to acquisition	$ 570

The estimated purchase price of an acquisition that has not closed by period end as disclosed.

No definition available.

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

- References

No definition available.

+ Details

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

- 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

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

- Definition

Total revenue reported by the acquired entity for its previous full fiscal year before the business acquisition.

+ References

No definition available.

+ Details

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

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

+ Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=mmm_ScottSafetyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: