Goodwill and Other Intangible Assets (Schedule of Other Intangible Assets) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	$ 43,971	$ 42,791
Accumulated Amortization	(37,626)	(34,644)
Net Intangible Assets	6,345	8,147
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	34,966	34,966
Accumulated Amortization	(31,961)	(29,670)
Net Intangible Assets	3,005	5,296
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	7,870	6,839
Accumulated Amortization	(5,042)	(4,577)
Net Intangible Assets	2,828	2,262
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	1,135	986
Accumulated Amortization	(623)	(397)
Net Intangible Assets	$ 512	$ 589