Premises and Equipment - Schedule of Future Minimum Rentals (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Premises [Member]
Future Contractual Minimum Rental Revenues On Leases [Line Items]
2013	$ 3,341
2014	3,166
2015	2,979
2016	2,795
2017	2,544
Therafter	17,070
Total	31,895
Equipment [Member]
Future Contractual Minimum Rental Revenues On Leases [Line Items]
2013	207
2014	18
2015	0
2016	0
2017	0
Therafter	0
Total	$ 225

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Future Minimum Rent Expense Corporate Office Leases Due

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Future Minimum Rent Expense Corporate Office Leases Due Current

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Future Minimum Rent Expense Corporate Office Leases Due In Five Years

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Future Minimum Rent Expense Corporate Office Leases Due In Four Years

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Future Minimum Rent Expense Corporate Office Leases Due In Three Years

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Future Minimum Rent Expense Corporate Office Leases Due In Two Years

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Future Minimum Rent Expense Corporate Office Leases Due Thereafter

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