INVESTMENTS, AVAILABLE-FOR-SALE SECURITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, continuous unrealized loss position, less than 12 months	$ 0	$ 0
Available-for-sale Securities Reconciliation [Abstract]
Amortized cost	15,942	17,842
Gross unrealized gains	610	380
Gross unrealized losses	1,045	1,071
Available-for-sale investments	15,507	17,151
Available-for-sale securities, unrealized loss positions
Aggregate fair value	14,455	16,329
Auction Rate Securities [Member]
Available-for-sale Securities Reconciliation [Abstract]
Amortized cost	15,942	17,842
Gross unrealized gains	610	380
Gross unrealized losses	1,045	1,071
Available-for-sale investments	15,507	17,151
Available-for-sale securities, unrealized loss positions
Aggregate fair value	$ 14,455	$ 16,329

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.

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This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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