Goodwill and Other Intangible Assets - Goodwill Rollforward (Details) $ in Millions	9 Months Ended
Sep. 30, 2025 USD ($)
Changes in the carrying value of goodwill by operating segment
Beginning balance	$ 7,980
Acquisitions	80
Reclassification to assets held for sale	(23)
Foreign currency and other	243
Ending balance	8,280
Goodwill Adjustment Due To Segment Reallocation, Adjusted Balance
Changes in the carrying value of goodwill by operating segment
Beginning balance	7,980
Water Infrastructure
Changes in the carrying value of goodwill by operating segment
Acquisitions	76
Reclassification to assets held for sale	0
Foreign currency and other	83
Ending balance	2,257
Water Infrastructure \| Goodwill Adjustment Due To Segment Reallocation, Adjusted Balance
Changes in the carrying value of goodwill by operating segment
Beginning balance	2,098
Applied Water
Changes in the carrying value of goodwill by operating segment
Acquisitions	0
Reclassification to assets held for sale	0
Foreign currency and other	20
Ending balance	904
Applied Water \| Goodwill Adjustment Due To Segment Reallocation, Adjusted Balance
Changes in the carrying value of goodwill by operating segment
Beginning balance	884
Measurement and Control Solutions
Changes in the carrying value of goodwill by operating segment
Acquisitions	0
Reclassification to assets held for sale	(23)
Foreign currency and other	123
Ending balance	2,263
Measurement and Control Solutions \| Goodwill Adjustment Due To Segment Reallocation, Adjusted Balance
Changes in the carrying value of goodwill by operating segment
Beginning balance	2,163
Water Solutions and Services
Changes in the carrying value of goodwill by operating segment
Acquisitions	4
Reclassification to assets held for sale	0
Foreign currency and other	17
Ending balance	2,856
Water Solutions and Services \| Goodwill Adjustment Due To Segment Reallocation, Adjusted Balance
Changes in the carrying value of goodwill by operating segment
Beginning balance	$ 2,835

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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