Earnings Per Common Share (Earnings Per Share Basic And Diluted) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share Basic And Diluted By Common Class [Line Items]
Net income available to common shareholders	$ 47,819	$ 44,666	$ 140,820	$ 127,631
Less: Earnings allocated to participating securities	(171)	(162)	(530)	(497)
Net income allocated to common shareholders	$ 47,648	$ 44,504	$ 140,290	$ 127,134
Weighted average common shares outstanding - basic (in shares)	89,888	89,759	89,850	88,318
Stock options and restricted stock (in shares)	464	451	471	406
Weighted-average common shares outstanding - diluted (in shares)	90,614	90,423	90,591	90,193
Earnings per common share, Basic (in dollars per share)	$ 0.53	$ 0.50	$ 1.56	$ 1.44
Earnings per common share, Diluted (in dollars per share)	$ 0.53	$ 0.49	$ 1.55	$ 1.41
Warrants - Series A1 and A2 [Member]
Earnings Per Share Basic And Diluted By Common Class [Line Items]
Warrants (in shares)	0	0	0	1,300
Warrants - other [Member]
Earnings Per Share Basic And Diluted By Common Class [Line Items]
Warrants (in shares)	262	213	270	169