EARNINGS PER SHARE (DETAILS) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Earnings Per Share Basic Two Class Method Abstract
Net income (loss)	$ 14,926	$ 28,783	$ 20,275	$ 48,143
Undistributed Earnings Allocated To Participating Securities	453	916	569	1,469
Net Income Loss Available To Common Stockholders Basic	14,473	27,867	19,706	46,674
Weighted average number of shares outstanding basic	57,560,000	60,308,000	57,549,000	59,719,000
Earnings Per Share Basic Undistributed	$ 0.25	$ 0.46	$ 0.34	$ 0.78
Earnings Per Share Diluted Two Class Method Abstract
Undistributed Earnings Allocated To Unvested Stockholders	(307)	(796)	(285)	(1,245)
Undistributed Earnings Reallocated To Unvested Stockholders	304	783	282	1,229
Interest On Convertible Senior Notes Due 2032 Net Of Tax	711	711	1,376	1,376
Interest On Convertible Senior Notes Due 2033 Net Of Tax			1	1
Net Income Loss Available To Common Stockholders Diluted	15,181	28,565	21,080	48,035
Weighted Average Number Diluted Shares Outstanding Adjustment Abstract
Incremental Common Shares Attributable To Conversion Of Debt Securities Convertible Senior Notes Due 2032	5,822,000	5,823,000	5,822,000	5,823,000
Incremental Common Shares Attributable To Conversion Of Debt Securities Convertible Senior Notes Due 2033	4,000	4,000	4,000	4,000
Incremental Common Shares Attributable To Share Based Payment Arrangements	594,000	1,005,000	608,000	801,000
Weighted Average Number Of Diluted Shares Outstanding	63,980,000	67,140,000	63,983,000	66,347,000
Earnings per share diluted	$ 0.24	$ 0.43	$ 0.33	$ 0.72
Stock Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount	1,732,550	1,797,876	2,482,193	3,291,806
Segment Continuing Operations [Member]
Earnings Per Share Basic Two Class Method Abstract
Income Loss From Continuing Operations	14,926	34,512	20,275	61,197
Undistributed Earnings Allocated To Participating Securities	453	1,113	569	1,905
Net Income Loss Available To Common Stockholders Basic	14,473	33,399	19,706	59,292
Weighted average number of shares outstanding basic	57,560,000	60,308,000	57,549,000	59,719,000
Earnings Per Share Basic Undistributed	$ 0.25	$ 0.55	$ 0.34	$ 0.99
Earnings Per Share Diluted Two Class Method Abstract
Undistributed Earnings Allocated To Unvested Stockholders	(307)	(987)	(285)	(1,668)
Undistributed Earnings Reallocated To Unvested Stockholders	304	971	282	1,647
Interest On Convertible Senior Notes Due 2032 Net Of Tax	711	711	1,376	1,376
Interest On Convertible Senior Notes Due 2033 Net Of Tax			1	1
Net Income Loss Available To Common Stockholders Diluted	15,181	34,094	21,080	60,648
Weighted Average Number Diluted Shares Outstanding Adjustment Abstract
Incremental Common Shares Attributable To Conversion Of Debt Securities Convertible Senior Notes Due 2032	5,822,000	5,823,000	5,822,000	5,823,000
Incremental Common Shares Attributable To Conversion Of Debt Securities Convertible Senior Notes Due 2033	4,000	4,000	4,000	4,000
Incremental Common Shares Attributable To Share Based Payment Arrangements	594,000	1,005,000	608,000	801,000
Weighted Average Number Of Diluted Shares Outstanding	63,980,000	67,140,000	63,983,000	66,347,000
Earnings per share diluted	$ 0.24	$ 0.51	$ 0.33	$ 0.91
Segment Discontinued Operations [Member]
Earnings Per Share Basic Two Class Method Abstract
Income Loss From Discontinued Operations	0	(5,729)	0	(13,054)
Undistributed Earnings Allocated To Participating Securities	0	0	0	0
Net Income Loss Available To Common Stockholders Basic	0	(5,729)	0	(13,054)
Weighted average number of shares outstanding basic	0	60,308,000	0	59,719,000
Earnings Per Share Basic Undistributed	$ 0	$ (0.09)	$ 0	$ (0.22)
Earnings Per Share Diluted Two Class Method Abstract
Undistributed Earnings Allocated To Unvested Stockholders	0	0	0	0
Undistributed Earnings Reallocated To Unvested Stockholders	0	0	0	0
Interest On Convertible Senior Notes Due 2032 Net Of Tax	0	0	0	0
Interest On Convertible Senior Notes Due 2033 Net Of Tax			0	0
Net Income Loss Available To Common Stockholders Diluted	$ 0	$ (5,729)	$ 0	$ (13,054)
Weighted Average Number Diluted Shares Outstanding Adjustment Abstract
Incremental Common Shares Attributable To Conversion Of Debt Securities Convertible Senior Notes Due 2032	0	0	0	0
Incremental Common Shares Attributable To Conversion Of Debt Securities Convertible Senior Notes Due 2033	0	0	0	0
Incremental Common Shares Attributable To Share Based Payment Arrangements	0	0	0	0
Weighted Average Number Of Diluted Shares Outstanding	0	60,308,000	0	59,719,000
Earnings per share diluted	$ 0	$ (0.09)	$ 0	$ (0.22)