Premises and Equipment - Schedule of Future Minimum Rentals (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Premises [Member]
Operating Leased Assets [Line Items]
2014	$ 3,257
2015	2,969
2016	2,758
2017	2,582
2018	2,330
Therafter	12,276
Total	26,172
Equipment [Member]
Operating Leased Assets [Line Items]
2014	56
2015	0
2016	0
2017	0
2018	0
Therafter	0
Total	$ 56

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Future Minimum Rent Expense Corporate Office Leases Due In Five Years

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