Contingencies and Environmental Remediation (Details) $ in Millions	Sep. 28, 2025 USD ($)
Contingencies and Environmental Remediation
Possible loss	$ 2.3

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 720
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-Name Accounting Standards Codification
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 460
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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-9

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-2

Name:	us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

WATTS WATER TECHNOLOGIES INC 10-Q