Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Jun. 21, 2010
Proforma Debt Instrument [Line Items]
Aggregate amount add back to future non-cash charges	$ 1,250	$ 1,250
Credit agreement, maturity date	Mar. 28, 2018
Either rate per annum equal to lower of prime rate Federal Funds effective rate plus half percent plus applicable margin	0.50%
Either rate per annum equal to lower of prime rate Federal Funds effective LIBOR plus one percent plus applicable margin	1.00%
Non-cash charges, including goodwill and other intangible asset impairment charges	250
Debt to total adjusted capitalization ratio	65.00%
Additional borrowing capacity	858
Absorption of reduction to shareholders' equity to remain in compliance with covenant	462
Maximum [Member]
Proforma Debt Instrument [Line Items]
Minimum interest coverage ratio	2.5
Minimum [Member]
Proforma Debt Instrument [Line Items]
Minimum interest coverage ratio	1.00
Euros Denominated Revolver [Member]
Proforma Debt Instrument [Line Items]
Borrowing capacity, maximum	500
Swingline Loans [Member]
Proforma Debt Instrument [Line Items]
Borrowing capacity, maximum	150
Letters of Credit [Member]
Proforma Debt Instrument [Line Items]
Borrowing capacity, maximum	250
Outstanding and unused Letters of Credit	$ 78

Absorption of reduction to shareholders' equity to remain in compliance with covenant.

No definition available.

Name:	mas_AbsorptionOfReductionToShareholdersEquityToRemainInComplianceWithCovenant
Namespace Prefix:	mas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Aggregate Amount Add Back To Future Non Cash Charges

+ References

No definition available.

+ Details

Name:	mas_AggregateAmountAddBackToFutureNonCashCharges
Namespace Prefix:	mas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Adjusted Capitalization Ratio

+ References

No definition available.

+ Details

Name:	mas_DebtAdjustedCapitalizationRatio
Namespace Prefix:	mas_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Either Rate Per Annum Equal To Lower Of Prime Rate Federal Funds Effective Libor Plus One Percent Plus Applicable Margin

+ References

No definition available.

+ Details

Name:	mas_EitherRatePerAnnumEqualToLowerOfPrimeRateFederalFundsEffectiveLiborPlusOnePercentPlusApplicableMargin
Namespace Prefix:	mas_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Either Rate Per Annum Equal To Lower Of Prime Rate Federal Funds Effective Rate Plus Half Percent Plus Applicable Margin

+ References

No definition available.

+ Details

Name:	mas_EitherRatePerAnnumEqualToLowerOfPrimeRateFederalFundsEffectiveRatePlusHalfPercentPlusApplicableMargin
Namespace Prefix:	mas_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility increase additional borrowing.

+ References

No definition available.

+ Details

Name:	mas_LineOfCreditFacilityIncreaseAdditionalBorrowing
Namespace Prefix:	mas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Minimum Interest Coverage Ratio

+ References

No definition available.

+ Details

Name:	mas_MinimumInterestCoverageRatio
Namespace Prefix:	mas_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Non Cash Charges Including Goodwill And Other Intangible Asset Impairment Charges

+ References

No definition available.

+ Details

Name:	mas_NonCashChargesIncludingGoodwillAndOtherIntangibleAssetImpairmentCharges
Namespace Prefix:	mas_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	mas_ProformaDebtInstrumentLineItems
Namespace Prefix:	mas_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-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.

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-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 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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