Fair Value of Financial Instruments (Carrying Value and Estimated Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fixed maturities:
Available-for-sale securities	$ 1,816,765	$ 1,825,438
Equity securities	193,263	206,685
Mortgage loans	47,494	47,614
Fair Value
Fixed maturities:
Available-for-sale securities	1,817,743
Equity securities	193,263	206,685
Mortgage loans	48,129	48,932
Other long-term investments	77,816	69,305
Short-term investments	804	175
Cash and cash equivalents	71,514	87,948
Corporate-owned life insurance	9,188	8,557
Liabilities
Long Term Debt	46,683	50,000
Fair Value \| Fixed maturities
Fixed maturities:
Available-for-sale securities	1,816,939	1,825,443
Carrying Value
Fixed maturities:
Available-for-sale securities	1,817,569
Equity securities	193,263	206,685
Mortgage loans	47,494	47,614
Other long-term investments	77,816	69,305
Short-term investments	804	175
Cash and cash equivalents	71,514	87,948
Corporate-owned life insurance	9,188	8,557
Liabilities
Long Term Debt	50,000	50,000
Carrying Value \| Fixed maturities
Fixed maturities:
Available-for-sale securities	$ 1,816,765	$ 1,825,438

Other Long-term Investments, Fair Value Disclosure

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Short-term Investments, Fair Value Disclosure

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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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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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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