Other Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012 LawSuits
Number of insulation installation contractors certified by the federal court in Atlanta	377
Amount paid for claims settlement	$ 75

Loss contingency settlement agreement consideration payable.

No definition available.

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