Commitments and Contingencies - Product Liability (Details)	12 Months Ended
Dec. 31, 2018 case lawsuit	Dec. 31, 2017 lawsuit
Product Liability - Bair Hugger
Product Liability Litigation
Number of lawsuits filed	5,015	4,270
Number of federal bellwether cases with trial-ready dates set	2
Number of federal bellwether cases in aggregate that have a scheduled trial date set	6
Number of federal bellwether cases dismissed	4
Number of federal bellwether cases still outstanding	1
Number of total claims dismissed \| case	61
Product Liability - Bair Hugger \| U.S. District Court for the Western District of Tennessee
Product Liability Litigation
Number of lawsuits filed \| case	1
Product Liability - Bair Hugger and medical malpractice claims \| Hidalgo County Texas
Product Liability Litigation
Number of lawsuits pending	1
Product Liability - Bair Hugger and medical malpractice claims \| Hidalgo County Texas and Ramsey County Minnesota in Aggregate [Member]
Product Liability Litigation
Number of lawsuits filed	2
Product Liability - Dual-Ended Combat Arms Earplugs
Product Liability Litigation
Number of lawsuits filed	26

This element represents the number of federal bellwether cases that have a scheduled trial date set.

No definition available.

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Namespace Prefix:	mmm_
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- Definition

This element represents the number of federal bellwether cases dismissed.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

This element represents the number of federal bellwether cases in aggregate that have a scheduled trial date set.

+ References

No definition available.

+ Details

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Namespace Prefix:	mmm_
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Period Type:	duration

- Definition

This element represents the number of federal bellwether cases still outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	mmm_
Data Type:	xbrli:integerItemType
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- Definition

Number of claims dismissed.

+ References

No definition available.

+ Details

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

- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- 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

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