Derivative Financial Instruments Derivative Financial Instruments (Rollforward Of Amounts In Accumulated Other Comprehensive Income Related To Interest Rate Swaps Designated As Cash Flow Hedges) (Detail) (Interest Rate Contract, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Interest Rate Contract
Rollforward of AOCI from Cash Flow Hedging Derivatives [Roll Forward]
Unrealized loss at beginning of period	$ (4,062)	$ (3,971)
Amount reclassified from accumulated other comprehensive income to interest expense on junior subordinated debentures	414	493
Amount of loss recognized in other comprehensive income	(975)	(591)
Unrealized loss at end of period	$ (4,623)	$ (4,069)