SUMMARY OF INVESTMENTS (Maturities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Trading, Amortized Cost
Amortized Cost	$ 11,941	$ 11,277
Trading, Fair Value
Fair Value	15,256	$ 13,240
Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Due in one year or less	56,316
Due after one year through five years	286,426
Due after five years through 10 years	481,310
Due after 10 years	556,850
Available-For-Sale, Fair Value
Due in one year or less	56,635
Due after one year through five years	293,956
Due after five years through 10 years	504,300
Due after 10 years	580,907
Trading, Amortized Cost
Due in one year or less	2,464
Due after one year through five years	6,967
Due after five years through 10 years	0
Due after 10 years	2,510
Trading, Fair Value
Due in one year or less	3,132
Due after one year through five years	8,586
Due after five years through 10 years	0
Due after 10 years	3,538
Fixed maturities \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	1,659,760
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	1,719,607
Trading, Amortized Cost
Amortized Cost	11,941
Trading, Fair Value
Fair Value	15,256
Asset-backed securities \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	314
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	750
Mortgage-backed securities \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	6,250
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	6,356
Collateralized mortgage obligations \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	272,294
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	$ 276,703

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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), with single maturity date and allocated without single maturity date, maturing in sixth fiscal year through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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