Goodwill and Other Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Goodwill [Line Items]
Gross goodwill		$ 943	$ 924
Accumulated Impairment Losses		(415)	(415)
Net goodwill	$ 509	528	509
Goodwill [Roll Forward]
Gross goodwill		943	924
Accumulated Impairment Losses		(415)	(415)
December 31, 2019	509
Acquisitions	14
Goodwill, Other Increase (Decrease)	5
September 30, 2020	528
Plumbing Products
Goodwill [Line Items]
Gross goodwill		585	566
Accumulated Impairment Losses		(340)	(340)
Net goodwill	245	245	226
Goodwill [Roll Forward]
Gross goodwill		585	566
Accumulated Impairment Losses		(340)	(340)
December 31, 2019	226
Acquisitions	14
Goodwill, Other Increase (Decrease)	5
September 30, 2020	245
Decorative Architectural Products
Goodwill [Line Items]
Gross goodwill		358	358
Accumulated Impairment Losses		(75)	(75)
Net goodwill	283	283	283
Goodwill [Roll Forward]
Gross goodwill		358	358
Accumulated Impairment Losses		$ (75)	$ (75)
December 31, 2019	283
Acquisitions	0
Goodwill, Other Increase (Decrease)	0
September 30, 2020	$ 283

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 before 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 increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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