SCHEDULE V - VALUATION AND QUALIFYING ACCOUNTS (Details) - Reinsurance recoverables: Allowance for uncollectible balances - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
VALUATION AND QUALIFYING ACCOUNTS
Balance at beginning of period	$ 10.2	$ 7.7	$ 7.8
Charged to costs and expenses	1.4	2.5	(0.2)
Charged to other accounts	0.0	0.0	0.0
Deductions described	0.0	0.0	0.1
Balance at end of period	$ 11.6	$ 10.2	$ 7.7

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

No definition available.

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column B))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column E))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-4

+ Details

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

+ References

+ Details

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense.

+ References

+ Details

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- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

+ References

+ Details

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- Details

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