FAIR VALUE OF FINANCIAL INSTRUMENTS (Carrying Value and Estimated Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investments
Held-to-maturity securities	$ 150	$ 150
Trading securities	23,273	20,034
Fair Value
Investments
Other long-term investments	49,352	51,769
Short-term investments	175	175
Cash and cash equivalents	95,562	89,194
Corporate-owned life insurance	4,029	2,592
Fair Value \| Fixed Maturities
Investments
Held-to-maturity securities	150	150
Available-for-sale securities	1,535,070	1,453,286
Trading securities	16,842	14,390
Fair Value \| Equity securities
Investments
Available-for-sale securities	280,913	246,370
Trading securities	6,431	5,644
Carrying Value
Investments
Other long-term investments	49,352	51,769
Short-term investments	175	175
Cash and cash equivalents	95,562	89,194
Corporate-owned life insurance	4,029	2,592
Carrying Value \| Fixed Maturities
Investments
Held-to-maturity securities	150	150
Available-for-sale securities	1,535,070	1,453,286
Trading securities	16,842	14,390
Carrying Value \| Equity securities
Investments
Available-for-sale securities	280,913	246,370
Trading securities	6,431	5,644
Discontinued Operations \| Fair Value
Investments
Mortgage loans	3,594	3,895
Policy loans	5,815	5,366
Other long-term investments	16,437	15,870
Cash and cash equivalents	15,851	21,659
Policy reserves
Annuity (accumulations)	591,702	646,764
Annuity (benefit payments)	147,038	144,283
Discontinued Operations \| Fair Value \| Fixed Maturities
Investments
Held-to-maturity securities	34	49
Available-for-sale securities	1,430,025	1,444,840
Discontinued Operations \| Fair Value \| Equity securities
Investments
Available-for-sale securities	23,653	24,046
Discontinued Operations \| Carrying Value
Investments
Mortgage loans	3,435	3,706
Policy loans	5,815	5,366
Other long-term investments	16,437	15,870
Cash and cash equivalents	15,851	21,659
Policy reserves
Annuity (accumulations)	611,866	666,711
Annuity (benefit payments)	93,560	95,129
Discontinued Operations \| Carrying Value \| Fixed Maturities
Investments
Held-to-maturity securities	34	48
Available-for-sale securities	1,430,025	1,444,840
Discontinued Operations \| Carrying Value \| Equity securities
Investments
Available-for-sale securities	$ 23,653	$ 24,046

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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