FAIR VALUE OF FINANCIAL INSTRUMENTS (Carrying Value and Estimated Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Investments
Held-to-maturity securities	$ 675	$ 404
Available-for-sale securities	3,061,208	3,088,922
Trading securities	16,975	20,928
Fair Value [Member]
Investments
Mortgage loans	4,237	4,559
Policy loans	5,618	5,916
Other long-term investments	54,151	50,424
Short-term investments	175	175
Cash and cash equivalents	106,449	90,574
Corporate-owned life insurance	1,716	918
Policy reserves
Annuity (accumulations)	707,190	865,802
Annuity (benefit payments)	131,899	176,592
Fair Value [Member] \| Fixed Maturities [Member]
Investments
Held-to-maturity securities	675	404
Available-for-sale securities	2,824,961	2,843,079
Trading securities	12,622	16,862
Fair Value [Member] \| Equity Securities [Member]
Investments
Available-for-sale securities	236,247	245,843
Trading securities	4,353	4,066
Carrying Value [Member]
Investments
Mortgage loans	3,961	4,199
Policy loans	5,618	5,916
Other long-term investments	54,151	50,424
Short-term investments	175	175
Cash and cash equivalents	106,449	90,574
Corporate-owned life insurance	1,716	918
Policy reserves
Annuity (accumulations)	744,931	863,606
Annuity (benefit payments)	95,467	99,121
Carrying Value [Member] \| Fixed Maturities [Member]
Investments
Held-to-maturity securities	672	397
Available-for-sale securities	2,824,961	2,843,079
Trading securities	12,622	16,862
Carrying Value [Member] \| Equity Securities [Member]
Investments
Available-for-sale securities	236,247	245,843
Trading securities	$ 4,353	$ 4,066

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Fair value portion of mortgage loans held-for-sale.

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