Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]

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- Definition

Available-for-sale Securities, Gross Unrealized Losses, Market Value of Bonds Percent of Amortized Cost

+ References

No definition available.

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- Definition

Available-for-sale Securities, Gross Unrealized Losses, Number of Securities, Debt Maturities, Twelve Months or Greater, Percent of Total

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

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-Publisher FASB
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

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.

+ References

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

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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Investments (Unrealized Losses) (Details)	3 Months Ended
Investments (Unrealized Losses) (Details)	Mar. 31, 2019 USD ($)	Mar. 31, 2020 USD ($) security	Jan. 01, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]
Securities, other-than-temporarily impaired	$ 0
Debt securities, held to maturity		$ 6,996,080,000		$ 7,106,245,000
Debt securities, available for sale		3,174,260,000		3,356,945,000
Valuation allowance for mortgage loans		$ 1,885,000	$ 1,200,000	$ 675,000	$ 675,000
Debt Securities
Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]
Gross unrealized losses, number of issues \| security		325
Gross unrealized losses, percentage of total debt		22.80%
Gross unrealized losses, market value as a percent of amortized cost		93.20%
Gross unrealized losses, number of securities with maturities of 12 months or greater \| security		8
Gross unrealized losses, number of securities with maturities of 12 months or greater (as a percentage)		2.50%
External Credit Rating, Investment Grade \| Debt Securities
Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]
Gross unrealized losses, number of securities rated investment grade \| security		295
Ozark National Life Insurance Company
Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]
Debt securities, held to maturity	265,200,000	$ 324,600,000
Debt securities, available for sale	$ 392,500,000	$ 388,100,000