FAIR VALUE OF FINANCIAL INSTRUMENTS (Carrying Value and Estimated Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investments
Held-to-maturity securities	$ 0	$ 150
Trading securities	13,240	16,842
Equity securities	248,361	287,344
Mortgage loans	25,782	0
Fair Value
Investments
Equity securities	248,361	287,344
Mortgage loans	26,021	0
Other long-term investments	37,077	49,352
Short-term investments	175	175
Cash and cash equivalents	64,454	95,562
Corporate-owned life insurance	4,907	4,029
Fair Value \| Fixed Maturities
Investments
Held-to-maturity securities	0	150
Available-for-sale securities	1,749,488	1,535,070
Trading securities	13,240	16,842
Carrying Value
Investments
Equity securities	248,361	287,344
Mortgage loans	25,782	0
Other long-term investments	37,077	49,352
Short-term investments	175	175
Cash and cash equivalents	64,454	95,562
Corporate-owned life insurance	4,907	4,029
Carrying Value \| Fixed Maturities
Investments
Held-to-maturity securities	0	150
Available-for-sale securities	1,749,488	1,535,070
Trading securities	13,240	16,842
Discontinued Operations \| Fair Value
Investments
Mortgage loans	0	3,594
Policy loans	0	5,815
Other long-term investments	0	16,437
Cash and cash equivalents	0	15,851
Policy reserves
Annuity (accumulations)	0	591,702
Annuity (benefit payments)	0	147,038
Discontinued Operations \| Fair Value \| Fixed Maturities
Investments
Held-to-maturity securities	0	34
Available-for-sale securities	0	1,430,025
Discontinued Operations \| Fair Value \| Equity securities
Investments
Available-for-sale securities	0	23,653
Discontinued Operations \| Carrying Value
Investments
Mortgage loans	0	3,435
Policy loans	0	5,815
Other long-term investments	0	16,437
Cash and cash equivalents	0	15,851
Policy reserves
Annuity (accumulations)	0	611,866
Annuity (benefit payments)	0	93,560
Discontinued Operations \| Carrying Value \| Fixed Maturities
Investments
Held-to-maturity securities	0	34
Available-for-sale securities	0	1,430,025
Discontinued Operations \| Carrying Value \| Equity securities
Investments
Available-for-sale securities	$ 0	$ 23,653

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Liability for Annuity Benefit Payments, Fair Value Disclosure

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

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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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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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

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