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

- Details

Name:	mas_DebtTextualAbstract
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- Definition

Financial covenants.

+ References

No definition available.

+ Details

Name:	mas_FinancialCovenants
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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Issued notes.

+ References

No definition available.

+ Details

Name:	mas_IssuedNotes
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Balance Type:	credit
Period Type:	instant

- Definition

Line of credit facility additional borrowing capacity.

+ References

No definition available.

+ Details

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

- 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

Premium paid on repurchase of notes.

+ References

No definition available.

+ Details

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

- Definition

Decrease for amounts repaid on the debt instrument for the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 4

-Section 08

-Paragraph f

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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/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 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 3: 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)(1))

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

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Interest rate stated in the contractual debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 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 210.5-02.19(b),22(b))

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

+ Details

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

Debt (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012 Financial_Covenants	Jul. 16, 2012 5.875% Notes and Debentures due July 15, 2012 [Member]	Jun. 30, 2012 5.875% Notes and Debentures due July 15, 2012 [Member]	Jun. 30, 2012 5.95% Notes and Debentures due March 15, 2022 [Member]	Mar. 05, 2012 5.95% Notes and Debentures due March 15, 2022 [Member]
Debt Instrument [Line Items]
Interest on notes			5.875%	5.95%
Issued notes	$ 400	$ 745			$ 400
Additional borrowing capacity after the retirement		900
Absorption of reduction to shareholders' equity to remain in compliance with covenant	302	487
Debt (Textual) [Abstract]
Effective interest rate for notes	6.50%
Financial covenants	2
Company repurchased Notes in open-market transactions	46
Premium paid on repurchase of notes	1
Additional borrowing capacity	561
Borrowings under Five Year Revolving Credit Agreement	$ 0