INCOME TAXES (Components of Deferred Tax Assets and Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Accruals and reserves	$ 2,645	$ 1,641
Tax credits	4,416	6,719
Fixed assets and intangibles, other than goodwill	3,913	3,402
Net operating losses	1,426	1,645
Stock-based compensation	11,023	7,131
Deferred revenue	2,560us-gaap_DeferredTaxAssetsDeferredIncome	1,448us-gaap_DeferredTaxAssetsDeferredIncome
Other	2,177us-gaap_DeferredTaxAssetsOther	1,517us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	28,160us-gaap_DeferredTaxAssetsGross	23,503us-gaap_DeferredTaxAssetsGross
Deferred tax liabilities
Intangible other than goodwill	(850)	(1,020)
Goodwill	(535)	(305)
Net deferred tax assets	26,775us-gaap_DeferredTaxAssetsLiabilitiesNet	22,178us-gaap_DeferredTaxAssetsLiabilitiesNet
As reported:
Current deferred tax asset	6,205	7,715
Non-current deferred tax assets	21,166	15,317
Non-current deferred tax liabilities	(596)	(854)
Net deferred tax assets	$ 26,775us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 22,178us-gaap_DeferredTaxAssetsLiabilitiesNet

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