Fair Value of Financial Instruments - Financial Instrument Not Carried at Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Level 1
Financial Assets
Other investments	$ 0.0	$ 0.0
Deposit asset on reinsurance	0.0	0.0
Financial Liabilities
Policyholders' account balances	0.0	0.0
Other policyholder funds	0.0	0.0
Reverse repurchase agreements		0.0
Short-term debt		0.0
Long-term debt	0.0	0.0
Level 2
Financial Assets
Other investments	33.8	0.0
Deposit asset on reinsurance	0.0	0.0
Financial Liabilities
Policyholders' account balances	0.0	0.0
Other policyholder funds	908.7	810.7
Reverse repurchase agreements		73.9
Short-term debt		0.0
Long-term debt	571.4	240.5
Level 3
Financial Assets
Other investments	187.9	170.9
Deposit asset on reinsurance	2,259.6	2,207.2
Financial Liabilities
Policyholders' account balances	4,861.8	4,940.3
Other policyholder funds	7.3	52.3
Reverse repurchase agreements		0.0
Short-term debt		249.0
Long-term debt	0.0	0.0
Carrying Value
Financial Assets
Other investments	218.4	167.4
Deposit asset on reinsurance	2,496.6	2,516.6
Financial Liabilities
Policyholders' account balances	4,996.3	5,039.7
Other policyholder funds	916.0	863.0
Reverse repurchase agreements		70.2
Short-term debt		249.0
Long-term debt	546.0	249.0
Fair Value
Financial Assets
Other investments	221.7	170.9
Deposit asset on reinsurance	2,259.6	2,207.2
Financial Liabilities
Policyholders' account balances	4,861.8	4,940.3
Other policyholder funds	916.0	863.0
Reverse repurchase agreements		73.9
Short-term debt		249.0
Long-term debt	$ 571.4	$ 240.5

Deposit Asset On Reinsurance Fair Value Disclosure

No definition available.

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- Definition

Fair Value of the liability as of the balance sheet date to the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported.

+ References

No definition available.

+ Details

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- Definition

Policyholder Funds Fair Value

+ References

No definition available.

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- References

No definition available.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

Amount of investments classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

The carrying value of securities purchased to be resold in reverse repurchase transactions as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

+ References

No definition available.

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