Summary Of Significant Accounting Policies (Schedule Of Supplemental Net Income Per Common Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounting Policies [Abstract]
Net income (loss) from continuing operations	$ 16,461	$ (1,860)	$ 25,900	$ 10,676	$ 4,702	$ 21,491	$ 5,607	$ 735	$ 51,177	$ 32,534	$ 11,725
Basic weighted average common shares outstanding (in shares)									39,591	39,077	33,861
Effect of dilutive instruments (in shares)									435	591	444
Diluted weighted average common shares outstanding (in shares)									40,026	39,668	34,305
Net income from continuing operations per common share
Net income from continued operations (in dollars per share)	$ 0.41	$ (0.05)	$ 0.65	$ 0.27	$ 0.12	$ 0.55	$ 0.14	$ 0.02	$ 1.29	$ 0.83	$ 0.34
Net income from continuing operations (in dollars per share)	$ 0.41	$ (0.05)	$ 0.65	$ 0.27	$ 0.12	$ 0.55	$ 0.14	$ 0.02	$ 1.28	$ 0.82	$ 0.34