Name:	mmm_AuctionRateSecuritiesGrossUnrealizedLossesPreTax
Namespace Prefix:	mmm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents pre-determined intervals (in days) during which liquidity for auction rate securities is typically provided by an auction process that resets the applicable interest rate 1.

No definition available.

Name:	mmm_AuctionRateSecuritiesPreDeterminedIntervalsDuringWhichLiquidityForAuctionRateSecuritiesIsTypicallyProvided1
Namespace Prefix:	mmm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the pre-determined intervals (in days) during which liquidity for auction rate securities is typically provided by an auction process that resets the applicable interest rate 2.

No definition available.

Name:	mmm_AuctionRateSecuritiesPreDeterminedIntervalsDuringWhichLiquidityForAuctionRateSecuritiesIsTypicallyProvided2
Namespace Prefix:	mmm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the pre-determined intervals (in days) during which liquidity for auction rate securities is typically provided by an auction process that resets the applicable interest rate 3.

No definition available.

Name:	mmm_AuctionRateSecuritiesPreDeterminedIntervalsDuringWhichLiquidityForAuctionRateSecuritiesIsTypicallyProvided3
Namespace Prefix:	mmm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the pre-determined intervals (in days) during which liquidity for auction rate securities is typically provided by an auction process that resets the applicable interest rate 4.

No definition available.

Name:	mmm_AuctionRateSecuritiesPreDeterminedIntervalsDuringWhichLiquidityForAuctionRateSecuritiesIsTypicallyProvided4
Namespace Prefix:	mmm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Percentage of asset-backed securities in the available for sale portfolio that were rated AAA or A-1+ by Standard and Poor's and/or Aaa or P-1 by Moody's and/or AAA or F1+ by Fitch.

No definition available.

Name:	mmm_AvailableForSaleAssetBackedSecuritiesPercentageOfSecuritiesDisclosure
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the estimated fair value of auction-rate securities.

No definition available.

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

Represents the estimated fair value of current plus long-term asset-backed securities.

No definition available.

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

Represents the minimum period that auction rate securities have been in a loss position.

No definition available.

Name:	mmm_MinimumPeriodThatAuctionRateSecuritiesHaveBeenInLossPosition
Namespace Prefix:	mmm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the percentage of interests in auction rate securities to portfolio, maximum (as a percent).

No definition available.

Name:	mmm_PercentageOfInterestsInAuctionRateSecuritiesToPortfolioMaximum
Namespace Prefix:	mmm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

-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 Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13, 19

-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.

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

This item represents the gross unrealized losses for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

No definition available.