Earnings Per Share (Reconciliation Of Amounts Used To Calculate Basic And Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Per 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 [Abstract]
Income (loss) from continuing operations	$ 51,305	$ 9,180	$ 22,609	$ (99,664)
Provision for income taxes from discontinued operations	28	127	55	253
Loss from discontinued operations	(28)	(127)	(55)	(253)
Net income (loss)	$ 51,277	$ 9,053	$ 22,554	$ (99,917)
Weighted average number of common shares outstanding	36,478	35,983	36,392	35,742
Income (loss) from continuing operations (in $/share)	$ 1.41	$ 0.26	$ 0.62	$ (2.79)
Loss from discontinued operations (in $/share)	$ 0.00	$ (0.01)	$ 0.00	$ (0.01)
Net income (loss) per share of common stock	$ 1.41	$ 0.25	$ 0.62	$ (2.80)
Effect of dilutive securities (in shares)	716	725	730	0
Weighted average number of common and common equivalent shares outstanding	37,194	36,708	37,122	35,742
Income (loss) from continuing operations (in $/share)	$ 1.38	$ 0.25	$ 0.61	$ (2.79)
Loss from discontinued operations	$ 0.00	$ 0.00	$ 0.00	$ (0.01)
Net income (loss) per share of common stock	$ 1.38	$ 0.25	$ 0.61	$ (2.80)