Shareholders' Equity And Earnings Per Share (Components Of Other Comprehensive Income (Loss)) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Activity Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Unrealized Gains (Losses) on Securities, Beginning Balance	$ 5,907	$ 10,369	$ 4,204	$ 2,679
Other comprehensive income during the period, Accumulated Unrealized Gains (Losses) on Securities	2,111	510	3,814	8,200
Accumulated Unrealized Gains (Losses) on Securities, Ending Balance	8,018	10,879	8,018	10,879
Accumulated Unrealized Gains (Losses) on Derivative Instruments, Beginning Balance	(6,037)	(6,237)	(7,082)	(8,191)
Other comprehensive income during the period, Accumulated Unrealized Gains (Losses) on Derivative Instruments	(174)	(1,171)	871	783
Accumulated Unrealized Gains (Losses) on Derivative Instruments, Ending Balance	(6,211)	(7,408)	(6,211)	(7,408)
Accumulated Unrealized Gains (Losses) on Derivative Instruments, Beginning Balance	2,101	0	0	0
Other comprehensive income during the period, Accumulated Unrealized Gains (Losses) on Derivative Instruments	5,897	0	7,998	0
Accumulated Unrealized Gains (Losses) on Derivative Instruments, Ending Balance	7,998	0	7,998	0
Total Accumulated Other Comprehensive Income (Loss), Beginning of period	1,971	4,132	(2,878)	(5,512)
Other comprehensive income during the period, Total Accumulated Other Comprehensive Income (Loss)	7,834	(661)	12,683	8,983
Total Accumulated Other Comprehensive Income (Loss), End of period	$ 9,805	$ 3,471	$ 9,805	$ 3,471