ACCOUNTING POLICIES - Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Receivables
Certain receivables allowances including allowances for doubtful accounts	$ 36	$ 33

Represents current accounts receivables allowances including allowances for doubtful accounts.

No definition available.

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