Net Earnings (Loss) Per Share (Summary Of Basic And Diluted Earnings (Loss) Per Share) (Details) (USD $) In Thousands, except Per 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 And Diluted [Line Items]
Net income (loss)	$ (1,855)	$ 4,959	$ 2,273	$ 4,731	$ (4,693)	$ 3,139	$ (8,188)	$ 3,851	$ 10,108	$ (5,891)	$ 32,212
Weighted-average common shares outstanding									37,496	37,031	36,208
Net earnings (loss) per share, basic	$ (0.05)	$ 0.13	$ 0.06	$ 0.13					$ 0.27	$ (0.16)	$ 0.89
Effect of assumed exercise of stock options, warrants and RSUs									1,908		1,905
Weighted-average common shares outstanding, assuming dilution									39,404	37,031	38,113
Net earnings (loss) per share, diluted	$ (0.05)	$ 0.13	$ 0.06	$ 0.12					$ 0.26	$ (0.16)	$ 0.85
Outstanding options, warrants and RSUs excluded as impact would be antidilutive									32	3,779	362
Stock Options [Member]
Earnings Per Share Basic And Diluted [Line Items]
Weighted-average effect of dilutive securities									1,609		1,297
RSUs [Member]
Earnings Per Share Basic And Diluted [Line Items]
Weighted-average effect of dilutive securities									296		601
Warrants [Member]
Earnings Per Share Basic And Diluted [Line Items]
Weighted-average effect of dilutive securities									3		7