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REVENUE (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
REVENUE (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Net sales	$ 1,860	$ 1,983	$ 1,764	$ 1,581	$ 1,639	$ 1,716	$ 1,839	$ 1,513	$ 7,188	$ 6,707	$ 6,654
Performance obligation satisfied in previous period									7	2	4
Contract with customer, asset, gross, current	2				2				2	2
Contract with customer, liability	$ 62				$ 40				62	40
North America
Disaggregation of Revenue [Line Items]
Net sales									5,805	5,328	5,208
International, principally Europe
Disaggregation of Revenue [Line Items]
Net sales									1,383	1,379	1,446
Plumbing Products
Disaggregation of Revenue [Line Items]
Net sales									4,136	3,984	3,998
Plumbing Products \| North America
Disaggregation of Revenue [Line Items]
Net sales									2,753	2,605	2,552
Plumbing Products \| International, principally Europe
Disaggregation of Revenue [Line Items]
Net sales									1,383	1,379	1,446
Decorative Architectural Products
Disaggregation of Revenue [Line Items]
Net sales									3,052	2,723	2,656
Decorative Architectural Products \| North America
Disaggregation of Revenue [Line Items]
Net sales									3,052	2,723	2,656
Decorative Architectural Products \| International, principally Europe
Disaggregation of Revenue [Line Items]
Net sales									$ 0	$ 0	$ 0