COMMITMENTS AND CONTINGENCIES - Narrative (Details)	12 Months Ended				1 Months Ended		12 Months Ended				0 Months Ended					132 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Apr. 30, 2013	Dec. 31, 2012 USD ($)	May 31, 2012 Regulatory violations USD ($)	Apr. 30, 2012 Regulatory violations USD ($)	Apr. 30, 2013 Regulatory violations violation	Dec. 31, 2014 Exton, Pennsylvania and Vancouver, Canada USD ($)	Dec. 31, 2013 Exton, Pennsylvania and Vancouver, Canada USD ($)	Dec. 31, 2012 Exton, Pennsylvania and Vancouver, Canada USD ($)	May 31, 2007 Fremont, California USD ($)	Dec. 31, 2014 Fremont, California USD ($)	May 31, 2007 Fremont, California Financial standby letter of credit USD ($)	Dec. 31, 2014 Financial standby letter of credit USD ($)	Dec. 31, 2014 Vortek Industries	Dec. 31, 2014 Royalty agreements Vortek Industries CAD	Dec. 31, 2014 Royalty agreements Vortek Industries USD ($)
Loss Contingencies [Line Items]
General length of product warranty	12 months
Rent expense	$ 4,100,000	$ 3,900,000		$ 4,300,000
Sublease revenue								226,000	377,000	403,000
Term of contract											10 years
Operating lease initial base rent cost											1,400,000
Annual rent increase percentage											3.50%
Operating leases, future minimum payments, at end of lease term	716,000											1,500,000
Standby letter of credit													1,500,000
Maximum potential amount required to pay under outstanding standby letters of credit														1,700,000
Restricted cash	1,993,000	2,087,000
Royalty guarantees payments, percentage of net sales from certain Flash RTP products															1.40%
Potential cash payment to Canadian Minister of Industries from certain Flash RTP products in connection with acquisition of Vortek Industries, Ltd.																14,300,000	12,300,000
Cumulative royalty charges to date																400,000
Civil penalty						900,000
Payment for civil penalty					300,000
Remaining civil penalty contingency					$ 600,000
Suspended payment period for remaining civil penalty			1 year
Number of violations							0