Derivatives (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2013 CounterParties	Dec. 31, 2012
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	$ 103	$ 103	$ 72
Fair Value of Derivative Instruments, Liabilities	58	58	106
Year-on-year currency effects impact on net income, including hedging impact	(12)	(18)
Year-on-year derivative and other transaction gains and (losses) impact	(3)	10
Number of primary derivative counterparties		8
Number of master netting agreements supported by primary counterparty's parent guarantee		1
Number of credit support agreements by primary counterparty		7
Derivatives designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	69	69	62
Fair Value of Derivative Instruments, Liabilities	34	34	86
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	54	54	39
Derivatives designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	33	33	85
Derivatives designated as hedging instruments \| Commodity price swap contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	0	0	0
Derivatives designated as hedging instruments \| Commodity price swap contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	1	1	1
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	15	15	23
Derivatives designated as hedging instruments \| Interest rate swap contracts \| Other liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	0	0	0
Derivatives not designated as hedging instruments
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	34	34	10
Fair Value of Derivative Instruments, Liabilities	24	24	20
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current assets
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Assets	34	34	10
Derivatives not designated as hedging instruments \| Foreign currency forward/option contracts \| Other current liabilities
Location and Fair Value Amount of Derivative Instruments
Fair Value of Derivative Instruments, Liabilities	$ 24	$ 24	$ 20

Number of primary derivaties counterparties that 3M has credit support agreements with primary counterparties parent.

No definition available.

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

- Definition

Number of primary derivaties counterparties that 3M has master netting agreement with that is supported by primary counterparties parent guarantee.

+ References

No definition available.

+ Details

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

- Definition

Number of primary derivaties counterparties that 3M has credit support agreements in place with.

+ References

No definition available.

+ Details

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

- Definition

The year-on-year currency effects, including hedging impacts, on net income attributable to 3M. This estimate includes the effect of translating profits from local currencies into U.S. dollars; the impact of currency fluctuations on the transfer of goods between 3M operations in the United States and abroad; and transaction gains and losses, including derivative instruments designed to reduce foreign currency exchange rate risks.

+ References

No definition available.

+ Details

Name:	mmm_YearOnYearCurrencyEffectsImpactOnNetIncome
Namespace Prefix:	mmm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The year-on-year derivative and other transaction gains and losses impact on net income attributable to the parent.

+ References

No definition available.

+ Details

Name:	mmm_YearOnYearDerivativeAndOtherTransactionGainLossImpactOnNetIncome
Namespace Prefix:	mmm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

+ Details

Name:	us-gaap_DerivativeFairValueOfDerivativeAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

+ Details

Name:	us-gaap_DerivativeFairValueOfDerivativeLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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