COMPUTATION OF EARNINGS (LOSS) PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Information related to EPS computation
Series A 3% Redeemable Convertible Preferred Stock, dividend rate (as a percent)	3.00%	3.00%	3.00%	3.00%
Net income allocated to common stockholders (in dollars)	$ (7,708)	$ 11,377	$ 2,557	$ 23,456
Basic:
Weighted-average common shares outstanding	28,081	27,639	28,130	27,648
Basic (in dollars per share)	$ (0.27)	$ 0.34	$ 0.08	$ 0.70
Diluted:
Weighted-average shares outstanding used in basic calculation	28,081	27,639	28,130	27,648
Dilutive effect of options	0	182	291	210
Dilutive effect of unvested restricted stock	0	113	415	145
Weighted-average common stock and common stock equivalents	28,081	27,934	28,836	28,003
Diluted (in dollars per share)	$ (0.27)	$ 0.34	$ 0.07	$ 0.69
Common Stock
Information related to EPS computation
Net income allocated to common stockholders (in dollars)	(7,708)	9,402	2,121	19,385
Series A 3% Redeemable Convertible Preferred Stock
Information related to EPS computation
Series A 3% Redeemable Convertible Preferred Stock, dividend rate (as a percent)	3.00%	3.00%	3.00%	3.00%
Net income allocated to common stockholders (in dollars)	$ 0	$ 1,975	$ 436	$ 4,071
Diluted:
Stock issuable upon conversion of the Series A Preferred Stock	5,806	5,806	5,806	5,806
Stock awards excluded from calculation as their effect would be anti-dilutive	849	1,356	798	1,154