INVESTMENTS - (Summary of Amortized Cost and Fair Value of Debt and Equity Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt securities - available-for-sale:
Amortized Cost or Cost	$ 324,861	$ 473,126
Fair value	327,532	488,210
United States government obligations and authorities
Debt securities - available-for-sale:
Amortized Cost or Cost	90,750	169,947
Gross Unrealized Gains	625	1,866
Gross Unrealized Losses	683	38
Fair value	90,692	171,775
Obligations of states and political subdivisions
Debt securities - available-for-sale:
Amortized Cost or Cost	19,031	21,560
Gross Unrealized Gains	391	704
Gross Unrealized Losses	144	0
Fair value	19,278	22,264
Corporate securities
Debt securities - available-for-sale:
Amortized Cost or Cost	186,489	254,618
Gross Unrealized Gains	4,413	11,989
Gross Unrealized Losses	1,922	79
Fair value	188,980	266,528
International securities
Debt securities - available-for-sale:
Amortized Cost or Cost	28,591	27,001
Gross Unrealized Gains	212	659
Gross Unrealized Losses	221	17
Fair value	28,582	27,643
Debt securities
Debt securities - available-for-sale:
Amortized Cost or Cost	324,861	473,126
Gross Unrealized Gains	5,641	15,218
Gross Unrealized Losses	2,970	134
Fair value	$ 327,532	$ 488,210

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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Amortized cost 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 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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