Earnings Per Common Share (Computation Of Basic And Diluted Earnings (Loss) Per Common Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
NUMERATORS:
Net income	$ 52,546	$ 58,989	$ 17,221	$ 18,764	$ 25,270	$ 23,477	$ 26,253	$ 23,361	$ 147,520	$ 98,361	$ 101,891
Net earnings available to common shareholders	146	142	83	113	212	196	197	183	484	788	682
Net earnings available to common shareholders	$ 52,400	$ 58,847	$ 17,138	$ 18,651	$ 25,058	$ 23,281	$ 26,056	$ 23,178	$ 147,036	$ 97,573	$ 101,209
DENOMINATORS:
Weighted average number of common shares outstanding - basic									186,550	111,938	111,935
Effect of potentially dilutive common shares									994	238	216
Weighted average number of common shares outstanding - diluted									187,544	112,176	112,151
EARNINGS PER COMMON SHARE:
Basic earnings per common share (usd per share)	$ 0.24	$ 0.27	$ 0.09	$ 0.17	$ 0.22	$ 0.21	$ 0.23	$ 0.21	$ 0.79	$ 0.87	$ 0.90
Diluted earnings per common share (usd per share)	$ 0.24	$ 0.27	$ 0.09	$ 0.17	$ 0.22	$ 0.21	$ 0.23	$ 0.21	$ 0.78	$ 0.87	$ 0.90