Warranty - Changes in Warranty Liability (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Warrant Liability [Abstract]
Balance at beginning of period	$ 118	$ 102
Accruals for warranties issued during the period	18	42
Accruals related to pre-existing warranties	4	16
Settlements made (in cash or kind) during the period	(20)	(38)
Other, net	1	(4)
Balance at end of period	$ 121	$ 118

Standard product warranty accrual other net.

No definition available.

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

- Details

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

- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)(1),(c)(5)

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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

- Definition

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(2))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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

- Definition

Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard product warranties (including adjustments related to changes in estimates). Does not include any Increase or Decrease in the liability for accruals related to extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(4))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

Name:	us-gaap_StandardProductWarrantyAccrualPreexistingIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(3))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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