Goodwill and Other Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Goodwill [Line Items]
Gross goodwill		$ 964	$ 978
Accumulated Impairment Losses		(376)	(415)
Net goodwill	$ 588	588	563
Goodwill [Roll Forward]
Gross goodwill		964	978
Accumulated Impairment Losses		(376)	(415)
December 31, 2020	563
Acquisitions	35
Goodwill, Other Increase (Decrease)	(10)
March 31, 2021	588
Goodwill, Written off Related to Sale of Business Unit	39
Plumbing Products (A)
Goodwill [Line Items]
Gross goodwill		598	613
Accumulated Impairment Losses		(301)	(340)
Net goodwill	273	297	273
Goodwill [Roll Forward]
Gross goodwill		598	613
Accumulated Impairment Losses		(301)	(340)
December 31, 2020	273
Acquisitions	34
Goodwill, Other Increase (Decrease)	(10)
March 31, 2021	297
Decorative Architectural Products
Goodwill [Line Items]
Gross goodwill		366	365
Accumulated Impairment Losses		(75)	(75)
Net goodwill	290	291	290
Goodwill [Roll Forward]
Gross goodwill		366	365
Accumulated Impairment Losses		$ (75)	$ (75)
December 31, 2020	290
Acquisitions	1
Goodwill, Other Increase (Decrease)	0
March 31, 2021	$ 291

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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