Available for Sale Securities, Gross Unrealized Losses, Number of Securities as a Percentage of Total Debt

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Debt Securities, Available-For-Sale Securities, Gross Unrealized Losses, Market Value Of Bonds Percent Of Amortized Cost

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Debt Securities, Available-For-Sale Securities, Gross Unrealized Losses, Number Of Securities, Debt Maturities, Twelve Months Or Greater, Percent Of Total

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- Definition

Investments, Percentage of Gains on Bonds, Due to Calls of Securities

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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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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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- Definition

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 addition to investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, classified as other.

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Amount of long-term investments classified as other.

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The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

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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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Investments - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
Investments - Narrative (Details) $ in Thousands	Jun. 30, 2022 USD ($)	Jun. 30, 2021	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)	Jun. 30, 2022	Jun. 30, 2022 issue	Jun. 30, 2022 security
Schedule of Investments [Line Items]
Percentage of gains on bonds due to calls of securities	77.70%	100.00%	92.50%	100.00%
Debt securities, available-for-sale	$ 8,160,952		$ 8,160,952		$ 9,068,946
Loans originated during the year			44,100	$ 70,300	183,600
Other long-term investments	158,859		158,859		137,670
Ozark National Holdings
Schedule of Investments [Line Items]
Debt securities, available-for-sale	709,300		709,300		823,000
Mortgage Loan Investment
Schedule of Investments [Line Items]
Loan investments made by reinsurer	18,700		18,700		8,500
Real Estate
Schedule of Investments [Line Items]
Other long-term investments	$ 28,200		28,200		$ 28,600
Operating income from real estate			1,500	$ 1,400
Total net gain			$ 300
Debt Securities
Schedule of Investments [Line Items]
Gross unrealized losses, number of issues							930	930
Gross unrealized losses, percentage of total debt						76.60%
Gross unrealized losses, market value as a percent of amortized cost						92.20%
Gross unrealized losses, number of securities with maturities of 12 months or greater \| security								37
Gross unrealized losses, number of securities with maturities of 12 months or greater percentage						4.00%
Debt Securities \| External Credit Rating, Investment Grade
Schedule of Investments [Line Items]
Gross unrealized losses, number of issues \| security								914