INVESTMENTS (Available For Sale Securities) (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Securities, Available-for-sale [Line Items]
Realized gain on investments	$ 0	$ 0	$ 0
Realized loss on investments	0	0	$ 0
Amortized Cost	10,800,000	10,800,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(730,000)	(730,000)
Fair Value	10,070,000	10,070,000
Aggregate Fair Value	10,070,000	10,070,000
Gross Unrealized Losses	(730,000)	(730,000)
Auction Rate Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	10,800,000	10,800,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(730,000)	(730,000)
Fair Value	10,070,000	10,070,000
Aggregate Fair Value	10,070,000	10,070,000
Gross Unrealized Losses	$ (730,000)	$ (730,000)

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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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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).

+ References

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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), in continuous unrealized loss position for more than 12 months.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

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Amount of realized gain 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 of realized loss 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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