Goodwill and Other Intangible Assets (Goodwill Rollforward) (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Changes in the carrying value of goodwill by operating segment
Balance as of January 1, 2020	$ 2,839
Foreign currency and other	(49)
Balance as of March 31, 2020	2,790
Water Infrastructure
Changes in the carrying value of goodwill by operating segment
Balance as of January 1, 2020	651
Foreign currency and other	(13)
Balance as of March 31, 2020	638
Applied Water
Changes in the carrying value of goodwill by operating segment
Balance as of January 1, 2020	513
Foreign currency and other	(5)
Balance as of March 31, 2020	508
Measurement & Control Solutions
Changes in the carrying value of goodwill by operating segment
Balance as of January 1, 2020	1,675
Foreign currency and other	(31)
Balance as of March 31, 2020	$ 1,644

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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