EARNINGS PER SHARE (DETAILS) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Earnings Per Share Basic Two Class Method Abstract
Net Income (Loss)	$ 58,946	$ 19,452	$ 28,783	$ 19,360	$ 23,888	$ 27,578	$ 36,500	$ 35,372	$ 126,540	$ 123,335	$ 75,951
Undistributed Earnings Allocated To Participating Securities									3,907	3,807	2,363
Net Income Loss Available To Common Stockholders Basic									122,633	119,528	73,588
Weighted average number of shares outstanding basic									60,183,000	58,430,000	57,252,000
Earnings Per Share Basic Undistributed									$ 2.04	$ 2.05	$ 1.29
Earnings Per Share Diluted Two Class Method Abstract
Undistributed Earnings Allocated To Unvested Stockholders									(3,600)	(3,450)	(2,099)
Undistributed Earnings Reallocated To Unvested Stockholders									3,554	3,430	2,096
Interest On Old Notes Net Of Tax									2,930	2,664	2,664
Interest On New Notes Net Of Tax									2	2	2
Net Income Loss Available To Common Stockholders Diluted									125,519	122,174	76,251
Weighted Average Number Diluted Shares Outstanding Adjustment Abstract
Incremental Common Shares Attributable To Conversion Of Debt Securities Old Notes									5,823,000	5,823,000	5,823,000
Incremental Common Shares Attributable To Conversion Of Debt Securities New Notes									4,000	4,000	4,000
Incremental Common Shares Attributable To Share Based Payment Arrangements									813,000	344,000	93,000
Weighted Average Number Of Diluted Shares Outstanding									66,823,000	64,601,000	63,172,000
Earnings per share diluted	$ 0.87	$ 0.29	$ 0.43	$ 0.30	$ 0.37	$ 0.42	$ 0.56	$ 0.54	$ 1.88	$ 1.89	$ 1.21
Stock Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount									2,552,489	8,356,506	10,329,552
Segment Continuing Operations [Member]
Earnings Per Share Basic Two Class Method Abstract
Income Loss From Continuing Operations									106,957	150,383	94,746
Undistributed Earnings Allocated To Participating Securities									3,276	4,663	2,956
Net Income Loss Available To Common Stockholders Basic									103,681	145,720	91,790
Weighted average number of shares outstanding basic									60,183,000	58,430,000	57,252,000
Earnings Per Share Basic Undistributed									$ 1.72	$ 2.49	$ 1.60
Earnings Per Share Diluted Two Class Method Abstract
Undistributed Earnings Allocated To Unvested Stockholders									(2,970)	(4,306)	(2,692)
Undistributed Earnings Reallocated To Unvested Stockholders									2,931	4,282	2,688
Interest On Old Notes Net Of Tax									2,930	2,664	2,664
Interest On New Notes Net Of Tax									2	2	2
Net Income Loss Available To Common Stockholders Diluted									106,574	148,362	94,452
Weighted Average Number Diluted Shares Outstanding Adjustment Abstract
Incremental Common Shares Attributable To Conversion Of Debt Securities Old Notes									5,823,000	5,823,000	5,823,000
Incremental Common Shares Attributable To Conversion Of Debt Securities New Notes									4,000	4,000	4,000
Incremental Common Shares Attributable To Share Based Payment Arrangements									813,000	344,000	93,000
Weighted Average Number Of Diluted Shares Outstanding									66,823,000	64,601,000	63,172,000
Earnings per share diluted									$ 1.59	$ 2.30	$ 1.50
Segment Discontinued Operations [Member]
Earnings Per Share Basic Two Class Method Abstract
Income Loss From Discontinued Operations									19,583	(27,048)	(18,795)
Undistributed Earnings Allocated To Participating Securities									462	0	0
Net Income Loss Available To Common Stockholders Basic									19,121	(27,048)	(18,795)
Weighted average number of shares outstanding basic									60,183,000	58,430,000	57,252,000
Earnings Per Share Basic Undistributed									$ 0.32	$ (0.46)	$ (0.33)
Earnings Per Share Diluted Two Class Method Abstract
Undistributed Earnings Allocated To Unvested Stockholders									0	0	0
Undistributed Earnings Reallocated To Unvested Stockholders									0	0	0
Interest On Old Notes Net Of Tax									0	0	0
Interest On New Notes Net Of Tax									0	0	0
Net Income Loss Available To Common Stockholders Diluted									$ 19,121	$ (27,048)	$ (18,795)
Weighted Average Number Diluted Shares Outstanding Adjustment Abstract
Incremental Common Shares Attributable To Conversion Of Debt Securities Old Notes									0	0	0
Incremental Common Shares Attributable To Conversion Of Debt Securities New Notes									0	0	0
Incremental Common Shares Attributable To Share Based Payment Arrangements									0	0	0
Weighted Average Number Of Diluted Shares Outstanding									60,183,000	58,430,000	57,252,000
Earnings per share diluted									$ 0.32	$ (0.46)	$ (0.33)