OTHER INCOME (EXPENSE), NET (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
OTHER INCOME (EXPENSE), NET
Income from cash and cash investments	$ 3mas_InterestIncome	$ 3mas_InterestIncome	$ 6mas_InterestIncome
Other interest income	1us-gaap_InterestIncomeOther	2us-gaap_InterestIncomeOther	1us-gaap_InterestIncomeOther
Income from financial investments, net (Note E)	2mas_IncomeFromInvestments	27mas_IncomeFromInvestments	22mas_IncomeFromInvestments
Foreign currency transaction gains (losses)	5	(18)	(2)
Other items, net	1	(2)	(2)
Total other, net	12us-gaap_OtherNonoperatingIncomeExpense	12us-gaap_OtherNonoperatingIncomeExpense	25us-gaap_OtherNonoperatingIncomeExpense
Currency translation expense related to sale of the ready-to-assemble cabinet business		$ 18

Represents the amount of currency translation expense related to sale of business.

No definition available.

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

- Definition

Represents income from investments, excluding interest.

+ References

No definition available.

+ Details

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

- Definition

Represents interest income on cash and cash investments and dividends.

+ References

No definition available.

+ Details

Name:	mas_InterestIncome
Namespace Prefix:	mas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the net of foreign currency translation gains/losses and other miscellaneous income/expense items, which is included as part of other non-operating income and expense.

+ References

No definition available.

+ Details

Name:	mas_OtherNonoperatingIncomeExpenseOtherIncomeExpenseItemsNet
Namespace Prefix:	mas_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450189&loc=d3e30690-110894

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6450189&loc=d3e30700-110894

+ Details

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

- Definition

Amount of interest income earned from interest bearing assets not separately disclosed.

+ References

No definition available.

+ Details

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

- Details

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

- Definition

The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.9)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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