Closed Block - Change in Maximum Future Earnings (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Change in maximum future earnings of the Closed Block
Maximum future earnings to be recognized from Closed Block assets and liabilities, beginning of year	$ 379.2	$ 393.5	$ 426.9
Effects of implementation of accounting changes			0.1
Maximum future earnings to be recognized from Closed Block assets and liabilities, end of year	344.5	379.2	393.5
Change in maximum future earnings	$ (34.7)	$ (14.3)	$ (33.3)

Amount of increase (decrease) in the carrying amount of closed block liabilities in excess of the carrying amount of closed block assets at the date of demutualization (adjusted to eliminate the impact of related amounts in accumulated other comprehensive income), resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

No definition available.

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- Definition

The carrying amount of closed block liabilities in excess of the carrying amount of closed block assets at the date of demutualization (adjusted to eliminate the impact of related amounts in accumulated other comprehensive income).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 55
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=124502525&loc=d3e31071-158570

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(9)
-URI https://asc.fasb.org/extlink&oid=124505872&loc=d3e30806-158569

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- Definition

Amount of increase (decrease) of closed block liabilities in excess of closed block assets at the date of demutualization.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(9)
-URI https://asc.fasb.org/extlink&oid=124505872&loc=d3e30806-158569

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 55
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=124502525&loc=d3e31071-158570

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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.

+ Details

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