Goodwill and Other Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Goodwill [Line Items]
Gross goodwill		$ 936	$ 924
Accumulated Impairment Losses		(415)	(415)
Net goodwill	$ 521	521	509
Goodwill [Roll Forward]
Gross goodwill		936	924
Accumulated Impairment Losses		(415)	(415)
Net Goodwill, December 31, 2019	509
Acquisitions	12
Net Goodwill, June 30, 2020	521
Plumbing Products
Goodwill [Line Items]
Gross goodwill		578	566
Accumulated Impairment Losses		(340)	(340)
Net goodwill	226	238	226
Goodwill [Roll Forward]
Gross goodwill		578	566
Accumulated Impairment Losses		(340)	(340)
Net Goodwill, December 31, 2019	226
Acquisitions	12
Net Goodwill, June 30, 2020	238
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)
Net Goodwill, December 31, 2019	283
Acquisitions	0
Net Goodwill, June 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 of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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 accumulated impairment loss for 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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