Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- 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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- 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
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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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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Namespace Prefix:	us-gaap_
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Balance Type:	na
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- 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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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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

- Details

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Name:	us-gaap_DebtInstrumentAxis=mmm_FixedRateMediumTermNoteDue2048Member
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Long-Term Debt and Short-Term Borrowings - Long-Term Debt Issuances (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended
	Sep. 30, 2018	Aug. 31, 2018	Sep. 30, 2018
Debt instrument
Repayment of debt		$ 450
Fixed rate medium term note due 2021
Debt instrument
Principal amount	$ 400		$ 400
Term of debt instrument	3 years
Interest rate - effective	3.00%		3.00%
Fixed rate medium term notes due 2024
Debt instrument
Principal amount	$ 300		$ 300
Term of debt instrument	5 years 6 months
Interest rate - effective	3.25%		3.25%
Floating rate medium term notes due 2024
Debt instrument
Principal amount	$ 300		$ 300
Term of debt instrument	5 years 6 months
Variable rate	three-month LIBOR
Fixed rate medium term notes due 2028
Debt instrument
Principal amount	$ 600		$ 600
Term of debt instrument	10 years
Interest rate - effective	3.625%		3.625%
Fixed rate medium term notes due 2048
Debt instrument
Principal amount	$ 650		$ 650
Term of debt instrument	30 years
Interest rate - effective	4.00%		4.00%
Interest rate swap contracts \| Fixed rate medium term note due 2021
Debt instrument
Derivative notional amount	$ 200		$ 200
Variable rate			three-month LIBOR