The number of interest rate swap contracts entered into during the period after a debt issuance.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

+ Details

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- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=mmm_FixedRateMediumTermNoteDue2019Member
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mmm_August2015MediumTermNotesIssuedMember
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Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mmm_June2014MediumTermNotesIssuedMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=mmm_FixedRateMediumTermNoteDue2021Member
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=mmm_FixedRateMediumTermNoteDue2018Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mmm_FixedRateMediumTermNoteDue2020Member
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Derivatives - Fair Value Hedges (Details) € in Millions, $ in Millions	1 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($)	Aug. 31, 2015 USD ($) DerivativeInstrument	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017 USD ($)	Jun. 30, 2014 USD ($)	Nov. 30, 2013 EUR (€)
Eurobond Due 2021
Derivatives in Fair Value Hedging Relationships
Principal amount \| €							€ 600
Fixed rate medium term note due 2019
Derivatives in Fair Value Hedging Relationships
Principal amount						$ 625.0
August 2015 medium term notes issued
Derivatives in Fair Value Hedging Relationships
Principal amount		$ 1,500.0
June 2014 medium term notes issued
Derivatives in Fair Value Hedging Relationships
Principal amount						950.0
Fixed rate medium term note due 2021
Derivatives in Fair Value Hedging Relationships
Principal amount	$ 400.0
Term of debt instrument	3 years
Variable rate			three-month LIBOR
Interest rate swap contracts \| Fixed rate medium term note due 2021
Derivatives in Fair Value Hedging Relationships
Derivative notional amount	$ 200.0
Variable rate				three-month LIBOR
Fair value hedges \| Interest rate swap contracts
Derivatives in Fair Value Hedging Relationships
Number of interest rate swap contracts entered in period \| DerivativeInstrument		2
Fair value hedges \| Interest rate swap contracts \| Eurobond Due 2021
Derivatives in Fair Value Hedging Relationships
Derivative notional amount \| €							€ 300
Fair value hedges \| Interest rate swap contracts \| Fixed rate medium term note due 2019
Derivatives in Fair Value Hedging Relationships
Derivative notional amount						$ 600.0
Variable rate			three-month LIBOR
Fair value hedges \| Interest rate swap contracts \| Fixed rate medium term note due 2018
Derivatives in Fair Value Hedging Relationships
Derivative notional amount		$ 450.0
Term of debt instrument		3 years
Fair value hedges \| Interest rate swap contracts \| Fixed rate medium term note due 2020
Derivatives in Fair Value Hedging Relationships
Derivative notional amount		$ 300.0			$ 200.0
Term of debt instrument		5 years
Variable rate			three-month LIBOR
Fair value hedges \| Interest rate swap contracts \| Fixed rate medium term note due 2021
Derivatives in Fair Value Hedging Relationships
Derivative notional amount	$ 200.0