MARKETABLE SECURITIES (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 93,301
Unrealized Gains	36
Unrealized Losses	(336)
Fair Value	93,001
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	44,802
Unrealized Gains	13
Unrealized Losses	(110)
Fair Value	44,705
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	48,499
Unrealized Gains	23
Unrealized Losses	(226)
Fair Value	$ 48,296

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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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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