Covered Loans - Composition of Covered Loans by Lending Classification (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Covered Loans [Line Items]
Covered loans	$ 217,832	$ 372,333
Allowance for loan losses	(5,404)
Covered loans, net	212,428
Commercial Loans [Member]
Covered Loans [Line Items]
Covered loans	29,335
Commercial Real Estate Loan [Member]
Covered Loans [Line Items]
Covered loans	81,928
Residential [Member]
Covered Loans [Line Items]
Covered loans	27,853
Consumer [Member]
Covered Loans [Line Items]
Covered loans	78,716
Covered Loans [Member]
Covered Loans [Line Items]
Covered loans	217,832
Loans Accounted for Under ASC 310-30 (Purchased Credit Impaired) [Member]
Covered Loans [Line Items]
Allowance for loan losses	(3,852)
Covered loans, net	131,038
Loans Accounted for Under ASC 310-30 (Purchased Credit Impaired) [Member] | Commercial Loans [Member]
Covered Loans [Line Items]
Covered loans	12,281
Loans Accounted for Under ASC 310-30 (Purchased Credit Impaired) [Member] | Commercial Real Estate Loan [Member]
Covered Loans [Line Items]
Covered loans	77,232
Loans Accounted for Under ASC 310-30 (Purchased Credit Impaired) [Member] | Residential [Member]
Covered Loans [Line Items]
Covered loans	27,704
Loans Accounted for Under ASC 310-30 (Purchased Credit Impaired) [Member] | Consumer [Member]
Covered Loans [Line Items]
Covered loans	17,673
Loans Accounted for Under ASC 310-30 (Purchased Credit Impaired) [Member] | Covered Loans [Member]
Covered Loans [Line Items]
Covered loans	134,890
Loans Excluded from ASC 310-30 (1) (Not Purchased Credit Impaired) [Member]
Covered Loans [Line Items]
Allowance for loan losses	(1,552)
Covered loans, net	81,390
Loans Excluded from ASC 310-30 (1) (Not Purchased Credit Impaired) [Member] | Commercial Loans [Member]
Covered Loans [Line Items]
Covered loans	17,054
Loans Excluded from ASC 310-30 (1) (Not Purchased Credit Impaired) [Member] | Commercial Real Estate Loan [Member]
Covered Loans [Line Items]
Covered loans	4,696
Loans Excluded from ASC 310-30 (1) (Not Purchased Credit Impaired) [Member] | Residential [Member]
Covered Loans [Line Items]
Covered loans	149
Loans Excluded from ASC 310-30 (1) (Not Purchased Credit Impaired) [Member] | Consumer [Member]
Covered Loans [Line Items]
Covered loans	61,043
Loans Excluded from ASC 310-30 (1) (Not Purchased Credit Impaired) [Member] | Covered Loans [Member]
Covered Loans [Line Items]
Covered loans	$ 82,942