Long-Duration Insurance Contracts - Deferred Sale Inducement Costs, Rollforward (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Movement in Deferred Sales Inducements [Roll Forward]
Balance, beginning of year	$ 15.9	$ 17.3
Capitalizations	0.0	0.0
Amortization expense	(0.3)	(0.3)
Experience adjustment	(0.2)	(0.1)
Balance, end of period	$ 15.4	$ 16.9

Amount of expense for writeoff from unexpected insurance contract termination, charged against previously capitalized deferred sale inducement cost.

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- Definition

Amount of deferred sale inducement cost capitalized.

+ References

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- Definition

Amount of amortization expense (reversal of expense) for deferred sales inducement cost.

+ References

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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of deferred sale inducement cost capitalized on contract remaining in force.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org//1943274/2147479432/944-30-50-2B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org//1943274/2147479460/944-30-45-2

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- Definition

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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