Investments - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Investment Holdings [Line Items]
Securities lending rate of collateral required	1.02
Fixed-maturities available for sale \| Debt Securities
Investment Holdings [Line Items]
Assets held by insurance regulators	$ 14.3	$ 16.9
Foreign government and agency securities
Investment Holdings [Line Items]
Securities lending rate of collateral required	1.05
Loaned securities
Investment Holdings [Line Items]
Securities lending rate of collateral required	1
Securities received as collateral	$ 57.8	$ 43.3

The rate of collateral required, expressed as a percentage of the fair value of the loaned securities.

No definition available.

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- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 825
-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=123600598&loc=SL75763979-209797

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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