Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Segment Information
Net sales	$ 1,970	$ 1,581
Operating Profit (Loss)	365	225
Other income (expense), net	(208)	(51)
Income from continuing operations before income taxes	157	174
North America
Segment Information
Net sales	1,529	1,258
International, principally Europe
Segment Information
Net sales	441	323
Plumbing Products (A)
Segment Information
Net sales	1,249	955
Plumbing Products (A) \| North America
Segment Information
Net sales	808	632
Plumbing Products (A) \| International, principally Europe
Segment Information
Net sales	441	323
Decorative Architectural Products
Segment Information
Net sales	721	626
Decorative Architectural Products \| North America
Segment Information
Net sales	721	626
Decorative Architectural Products \| International, principally Europe
Segment Information
Net sales	0	0
Operating Segments
Segment Information
Net sales	1,970	1,581
Operating Profit (Loss)	394	252
Operating Segments \| Plumbing Products (A)
Segment Information
Net sales	1,249	955
Operating Profit (Loss)	252	157
Operating Segments \| Decorative Architectural Products
Segment Information
Net sales	721	626
Operating Profit (Loss)	142	95
Geographic Areas
Segment Information
Net sales	1,970	1,581
Operating Profit (Loss)	394	252
Geographic Areas \| North America
Segment Information
Net sales	1,529	1,258
Operating Profit (Loss)	308	210
Geographic Areas \| International, principally Europe
Segment Information
Net sales	441	323
Operating Profit (Loss)	86	42
Corporate, Non-Segment
Segment Information
General corporate expense, net	$ (29)	$ (27)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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