EARNINGS (LOSS) PER SHARE (Antidilutive securities excluded from the computation of earnings (loss) per share) (Details)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents and outstanding stock options excluded from the calculation of diluted earnings (loss) per share (in thousands)	2,368,000	2,654,000	1,939,000	2,793,000	1,396,000	1,717,000	2,224,000	2,928,000	2,367,566	1,500,525	2,582,897
Unvested restricted stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents and outstanding stock options excluded from the calculation of diluted earnings (loss) per share (in thousands)									1,028,916	104,175	1,034,597
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents and outstanding stock options excluded from the calculation of diluted earnings (loss) per share (in thousands)									100,000	0	0
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents and outstanding stock options excluded from the calculation of diluted earnings (loss) per share (in thousands)									1,238,650	1,396,350	1,548,300