Goodwill And Other Intangible Assets (Summary of Finite-Lived Intangible Assets) (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Total other intangible assets, net	$ 25,533	$ 18,811	$ 19,984
Core deposit intangibles | Community banking
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	34,840	29,379	40,438
Accumulated amortization	(16,195)	(17,879)	(27,909)
Net carrying amount	18,645	11,500	12,529
Customer list intangibles | Specialty finance
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,800	1,800	1,800
Accumulated amortization	(1,027)	(941)	(910)
Net carrying amount	773	859	890
Customer list and other intangibles | Wealth management
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	7,940	7,940	7,940
Accumulated amortization	(1,825)	(1,488)	(1,375)
Net carrying amount	$ 6,115	$ 6,452	$ 6,565