The ratio of the market value of the collateralized eligible assets to the principal balance of the FHLB advances

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Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option

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Percent of Stock With Ordinary Voting Rights That Company Must Retain In Order To Make Any Capital Stock Transactions

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Maturity period on fixed rate advances made and reported by Federal Home Loan Bank (FHLBank), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank).

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Fair value of the amount outstanding under the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Borrowings and Financing Activities - Narrative (Details) - USD ($)	1 Months Ended				12 Months Ended
	Dec. 31, 2021	May 31, 2020	Jun. 30, 2019	Sep. 30, 2017	Dec. 31, 2021	Dec. 31, 2020
Term					10 years
Debt Securities \| Fixed-maturities available for sale
Investments serving as collateral for FHLB advances	$ 167,300,000				$ 167,300,000	$ 188,000,000
Senior notes \| Senior Notes due 2024
Debt instrument, face amount				$ 450,000,000
Proceeds from issuance of long-term debt				$ 442,200,000
Interest rate				4.50%
Senior notes \| Senior Notes due 2025
Debt instrument, face amount		$ 525,000,000
Proceeds from issuance of long-term debt		$ 515,600,000
Interest rate		6.625%
Senior notes \| Senior Notes due 2027
Debt instrument, face amount			$ 450,000,000
Proceeds from issuance of long-term debt			$ 442,200,000
Interest rate			4.875%
Senior notes \| Senior Notes Due 2024, 2025 and 2027
Redemption price percentage					100.00%
Basis spread on variable rate					0.50%
Percent of stock with ordinary voting rights	80.00%				80.00%
FHLB advances
Advances from FHLB	$ 150,983,000				$ 150,983,000	$ 176,483,000
FHLB weighted average interest rate	0.97%				0.97%
FHLB maturity period					90 days
Federal Home Loan Bank Certificates and Obligations (FHLB) \| Minimum
FHLB ratio of market value to collateral advances					1.03
Federal Home Loan Bank Certificates and Obligations (FHLB) \| Maximum
FHLB ratio of market value to collateral advances					1.14
Revolving Credit Facility
Line of credit facility, higher borrowing capacity option	$ 400,000,000				$ 400,000,000
Line of credit facility, fair value of amount outstanding	0				0
Revolving Credit Facility \| Unsecured Revolving Credit Facility, Expiration Date 2026
Line of credit facility, maximum borrowing capacity	$ 275,000,000				275,000,000
Term	5 years
Revolving Credit Facility \| Unsecured Revolving Credit Facility, Expiration Date 2022
Line of credit facility, maximum borrowing capacity	$ 267,500,000				$ 267,500,000