Significant Accounting Policies (Computation Of Basic And Diluted Earning Per Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounting Policies [Abstract]
Net income	$ 11,790	$ 9,393	$ 6,623	$ 2,666	$ 3,270	$ 2,825	$ (2,271)	$ 2,759	$ 30,472	$ 6,583	$ 33,220
Weighted average common shares									44,684,812	44,145,535	43,522,563
Employee stock-based compensation									736,328	546,310	626,491
Weighted average common shares assuming dilution									45,421,140	44,691,845	44,149,054
Earnings per share, Basic	$ 0.26	$ 0.21	$ 0.15	$ 0.06	$ 0.07	$ 0.06	$ (0.05)	$ 0.06	$ 0.68	$ 0.15	$ 0.76
Earnings per share, Diluted	$ 0.26	$ 0.21	$ 0.15	$ 0.06	$ 0.07	$ 0.06	$ (0.05)	$ 0.06	$ 0.67	$ 0.15	$ 0.75