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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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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 net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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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				9 Months Ended
Investments (Narrative) (Details) $ in Thousands	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Schedule of Investments [Line Items]
Real estate gain (loss)	$ 2,661	$ 0			$ 2,661	$ 6,888
Percentage of gains on bonds due to calls of securities	99.90%	99.60%			99.80%	81.00%
Debt securities, held to maturity	$ 6,827,139				$ 6,827,139		$ 7,106,245
Debt securities available for sale	3,410,656				3,410,656		3,356,945
Travis County
Schedule of Investments [Line Items]
Gain on sale of property	2,700
Ozark National Life Insurance Company [Member]
Schedule of Investments [Line Items]
Debt securities, held to maturity	335,300				335,300		307,200
Debt securities available for sale	416,000				$ 416,000		$ 415,700
Loans In Forbearance
Schedule of Investments [Line Items]
Number of loans \| loan					8
Loans receivable	$ 29,200				$ 29,200
Nursing Home Operations in Reno, Nevada
Schedule of Investments [Line Items]
Real estate gain (loss)				$ 5,700
Nursing Home Operations, San Marcos, Texas
Schedule of Investments [Line Items]
Real estate gain (loss)			$ (2,000)
Prior Home Office
Schedule of Investments [Line Items]
Real estate gain (loss)			$ 3,200