Net Income (Loss) Per Share (Computation Of Net Income (Loss) 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
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income	$ 6,164	$ 68,214	$ 1,580	$ 128,447
Weighted-average common shares outstanding	55,526	52,470	55,491	52,614
Basic earnings per share	$ 0.11	$ 1.30	$ 0.03	$ 2.44
Convertible Notes interest expense, net of tax	48	0	98	0
Numerator for diluted earning per share	$ 6,212	$ 68,214	$ 1,678	$ 128,447
Weighted-average number of shares	58,809	53,909	58,878	54,077
Diluted earnings per share	$ 0.11	$ 1.26	$ 0.03	$ 2.37
Convertible notes shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Employee stock options	2,331	0	2,331	0
Employee stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Employee stock options	952	1,439	1,056	1,463