Basis of Presentation and Significant Accounting Policies - Investment Contract and Life Policy Reserves (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Investment contract reserves	$ 5,117.0	$ 4,941.3
Policy reserves	1,851.0	1,636.5
Total	$ 6,968.0	$ 6,577.8

Amount, before effect of reinsurance, of present value of future benefit to be paid to or on behalf of policyholder and related expense less present value of future net premium receivable under insurance contract.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 40
-Section 50
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Amount of accrued obligation to policyholders that relates to insured events under individual and group annuities and supplementary insurance contracts.

+ References

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-Publisher FASB
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Amount of accrued obligation to policyholders that relates to insured events under long-term life insurance contracts.

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