INCOME TAXES (Effective Income Tax Rate Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Federal statutory rate	$ 4,945	$ (38)	$ 4,918
State taxes, net of federal income tax benefit	602	86	417
Non-deductible expenses	246	209	134
Stock-based compensation	2,209	1,535	701
Preferred stock warrant liability	0	0	966
Acquisition cost	0	110	0
Foreign tax deduction	(153)	(101)	0
Tax credits	(2,502)	(4,020)	(884)
Foreign tax rate differential	393	324	273
Other items not individually material	200	(4)	116
Change in statutory rate	0	0	(262)
Change in valuation allowance	0	0	(23,617)
Total income tax expense (benefit)	$ 5,940us-gaap_IncomeTaxExpenseBenefit	$ (1,899)us-gaap_IncomeTaxExpenseBenefit	$ (17,238)us-gaap_IncomeTaxExpenseBenefit

Effective Income Tax Rate Reconciliation, Acquisition

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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