GEOGRAPHIC AND CUSTOMER CONCENTRATION INFORMATION - Net Sales by Geographic Area (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	$ 126,526	$ 184,947	$ 138,336
Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	100.00%	100.00%	100.00%
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	17,476	10,311	7,211
United States | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	14.00%	6.00%	5.00%
Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	47,611	84,623	67,973
Korea | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	38.00%	46.00%	49.00%
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	28,577	37,507	18,878
Taiwan | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	23.00%	20.00%	14.00%
Other Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	22,177	33,112	36,856
Other Asia | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	17.00%	18.00%	27.00%
Europe and others
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, amount	$ 10,685	$ 19,394	$ 7,418
Europe and others | Geographic Concentration Risk | Net Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales, percentage	8.00%	10.00%	5.00%