Derivative Financial Instruments (Schedule Of Amounts Related To Interest Rate Derivatives Included In Income Designated As Hedges Of Cash Flows) (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
Interest Rate Swaps On Variable-Rate Loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive income to interest income on loans	$ 9,345	$ 9,345	$ 28,035	$ 28,035
Interest Rate Swaps On Junior Subordinated Deferrable Interest Debentures [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive income to interest expense on junior subordinated deferrable interest debentures	1,063	1,117	3,140	3,304
Amount of gain (loss) recognized in other comprehensive income	$ (269)	$ (908)	$ (760)	$ (2,560)