PROVISION FOR INCOME TAXES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Adjustments to additional paid in capital, benefit from employee stock option activity	$ (200)	$ 800	$ 1,300
U.S. and foreign components of income before income taxes [Abstract]
U.S. operations	(2,113)	(5,064)	1,936
Foreign operations	41,531	61,878	53,491
INCOME BEFORE INCOME TAXES	39,418	56,814	55,427
Current provision:
Federal	443	(1,234)	(558)
State	83	(137)	2
Foreign	5,407	3,094	3,049
Current provision	5,933	1,723	2,493
Deferred provision (benefit):
Federal	(1,699)	(3,279)	(3,633)
State	(57)	(284)	0
Foreign	(3,906)	(890)	(699)
Deferred provision (benefit)	(5,662)	(4,453)	(4,332)
Total	$ 271	$ (2,730)	$ (1,839)
Effective income tax rate reconciliation [Abstract]
Provision computed at Federal statutory rate	35.00%	35.00%	35.00%
State tax provision, net of Federal benefit	0.00%	0.00%	0.00%
Business tax credits	(6.80%)	(5.50%)	(8.10%)
Stock-based compensation	0.80%	(2.90%)	(2.80%)
Foreign income taxed at different rate	(33.10%)	(28.60%)	(29.50%)
IRS audit settlement	0.00%	(5.80%)	0.00%
Valuation allowance	2.60%	2.00%	(0.10%)
Other	2.20%	1.00%	2.20%
Total	0.70%	(4.80%)	(3.30%)
Components of deferred income tax asset [Abstract]
Other reserves and accruals	$ 1,573	$ 3,928
Tax credit carry-forwards	22,826	19,602
Stock compensation	5,945	5,429
Capital losses	11,490	11,401
Net operating loss	3,677	3,680
Valuation allowance	(26,918)	(25,828)
Deferred tax assets, net of valuation allowance	18,593	18,212
Depreciation	(2,968)	(3,320)
Acquired intangibles	0	(3,502)
Unremitted earnings	(4,626)	(5,182)
Other	(447)	(1,072)
Deferred tax liabilities	(8,041)	(13,076)
Net deferred tax asset	10,552	5,136
Reconciliation of the Beginning and Ending Amount of Unrecognized Tax Benefits [Roll Forward]
Unrecognized Tax Benefits, Balance at beginning of period	11,160	12,694	$ 10,813
Gross Increases for Tax Positions of Current Year	3,063	2,117	1,881
Gross Decrease for Tax Positions of Prior Years	(663)
Gross Increases for Tax Positions of Prior Years		710	0
Settlements	0	(4,361)	0
Lapse of Statute of Limitations	0	0	0
Unrecognized Tax Benefits, Balance at end of period	13,560	11,160	12,694
Unrecognized tax benefits [Abstract]
Undistributed earnings of the Company's foreign subsidiaries	222,000
Unrecognized Tax Benefits, Balance at end of period	13,560	11,160	$ 12,694
Income tax benefit that would be recorded if unrecognized tax benefits are recognized	5,600
Income tax interest and penalties accrued	100	100
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	25,100
State and Local Jurisdiction [Member] | California Taxing Authority [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	50,300
Research Tax Credit Carryforward [Member] | Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	12,700
Research Tax Credit Carryforward [Member] | State and Local Jurisdiction [Member] | California Taxing Authority [Member]
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	16,600
Research Tax Credit Carryforward [Member] | State and Local Jurisdiction [Member] | New Jersey Division of Taxation [Member]
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	600
Research Tax Credit Carryforward [Member] | Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	$ 1,900
Long-term Deferred Tax Assets [Member] | Accounting Standards Update 2013-07 [Member]
Operating Loss Carryforwards [Line Items]
Effect of adoption of new accounting principle		4,300
2007 through 2009 [Member] | Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards [Line Items]
Income tax liability (refund) adjustment from settlement with taxing authority		(3,300)
Reconciliation of the Beginning and Ending Amount of Unrecognized Tax Benefits [Roll Forward]
Settlements		(4,100)
2007 through 2009 [Member] | Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards [Line Items]
Income tax liability (refund) adjustment from settlement with taxing authority		(2,800)
2007 through 2009 [Member] | State and Local Jurisdiction [Member] | Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards [Line Items]
Income tax liability (refund) adjustment from settlement with taxing authority		$ (500)