Restructuring Charges (Restructuring Charges) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost and Impairment Charge
Severance and other charges	$ 26		$ 4	$ 46	$ 18
Lease related charges	0		0	1	1
Restructuring charges	26		4	48	19
Asset impairment	7		0	10	0
Total restructuring and asset impairment charges	33		4	58	19
Other Restructuring Costs	0		0	1	0
Water Infrastructure
Restructuring Cost and Impairment Charge
Restructuring charges	6		2	17	8
Applied Water
Restructuring Cost and Impairment Charge
Restructuring charges	2		1	4	2
Measurement & Control Solutions
Restructuring Cost and Impairment Charge
Restructuring charges	25		$ 1	$ 37	$ 9
Asset impairment	$ 7	$ 3

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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