Restructuring Charges (Restructuring Charges) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Restructuring Cost and Impairment Charge
Severance and other charges	$ 7	$ 9
Lease related charges	1	1
Restructuring charges	8	10
Asset impairment	3	0
Total restructuring and asset impairment charges	11	10
Water Infrastructure
Restructuring Cost and Impairment Charge
Restructuring charges	4	3
Applied Water
Restructuring Cost and Impairment Charge
Restructuring charges	0	1
Measurement & Control Solutions
Restructuring Cost and Impairment Charge
Restructuring charges	$ 7	$ 6

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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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Asset Impairment and Restructuring Charges

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