Investments - Narrative (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) mortgage_loan	Dec. 31, 2021 USD ($) mortgage_loan	Dec. 31, 2020 USD ($)
Schedule of Investments [Line Items]
Loans originated during the year	$ 47,400	$ 183,600
Number of mortgage loan \| mortgage_loan	3	3
Net investments in mortgage loans, after allowances for possible losses	$ 505,730	$ 487,304
Real estate investments	262,106	137,670
(Loss) gain on disposition of property	(1,400)	2,700
Debt securities, available-for-sale	7,611,633	9,068,946
Realized gains on investments	6,355	14,950	$ 21,071
Real Estate
Schedule of Investments [Line Items]
Real estate investments	27,700	28,600
Operating income recognized on real estate investment properties	3,000	2,900	2,900
Mortgage Loan Investment
Schedule of Investments [Line Items]
Loan investments made by reinsurer	19,300	8,500
Real Estate Investment
Schedule of Investments [Line Items]
Net gain	$ 1,200
US Treasury Bond Securities
Schedule of Investments [Line Items]
Increase in 10-year U.S. Treasury bond rate	2.37%
External Credit Rating, Non Investment Grade \| Debt Securities
Schedule of Investments [Line Items]
Debt securities, available-for-sale	$ 112,000	$ 153,000
Debt securities below investment grade, percentage of total invested assets	1.20%	1.40%
Non- Income Producing
Schedule of Investments [Line Items]
Real estate investment	$ 0	$ 100	$ 400
Ozark National Life Insurance Company:
Schedule of Investments [Line Items]
Debt securities, available-for-sale	$ 674,800	$ 823,000

Available-for-sale Securities and Held-to-maturity Securities, Percentage of Total Invested Assets

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Debt Securities, Available-for-Sale, Effective Interest Rate, Increase (Decrease)

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Number Of Mortgage Loan, Funds Withheld Reinsurance Agreement

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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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.

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