STOCKHOLDERS' EQUITY, Employee Stock Purchase Plan (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Employee Stock Purchase Plan [Abstract]
Employee purchase price, percent of market value	85.00%
Employee Stock Purchase Plan [Member]
Weighted-average assumptions and fair value of shares issued under the ESPP
Expected dividend yield (in hundredths)	0.00%	0.00%
Risk-free interest rate (in hundredths)	0.73%	0.23%
Expected volatility (in hundredths)	50.90%	40.90%
Expected life (in years)	0.25	0.24
Weighted-average fair value of shares issued (in dollars per share)	$ 1.49	$ 2.83
Shares issued under the ESPP (in shares)	72,145	40,915
Average price of shares issued (in dollars per share)	$ 7.77	$ 14.96