FAIR VALUE OF FINANCIAL INVESTMENTS AND LIABILITIES (Details 2) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income from financial investments, net and impairment charges
Equity investment (loss) income, net	$ (2,000,000)	$ 16,000,000
Income from financial investments, net	2,000,000mas_IncomeFromInvestments	27,000,000mas_IncomeFromInvestments	22,000,000mas_IncomeFromInvestments
Estimated market value of long-term and short-term debt	3,700,000,000us-gaap_DebtInstrumentFairValue	3,700,000,000us-gaap_DebtInstrumentFairValue
Aggregate carrying value of long-term and short-term debt	3,400,000,000	3,400,000,000
Private equity funds
Income from financial investments, net and impairment charges
Realized gains from private equity funds	4,000,000	11,000,000	24,000,000
Impairment of private equity funds			$ 2,000,000

Represents income from investments, excluding interest.

No definition available.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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No definition available.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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