Derivative Financial Instruments - Additional Information (Details) (Interest Rate Swap [Member], Not Designated as Hedging Instrument [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Customer
Customer interest rate swaps (commerical customer counterparty):
Notional amount of assets, Assets	$ 27,545	$ 28,190
Notional amount of assets, Liabilities	1,914	1,955
Notional amount of assets, Net total	29,459	30,145
Customer interest rate swaps (commerical customer counterparty):
Fair Value of assets, Assets	301	437
Fair Value of assets, Liabilities	(6)	(4)
Fair Value of assets, Net total	295	433
Correspondent
Correspondent interest rate swaps (financial institution counterparty):
Notional amount of liabilities, Assets	27,545	28,190
Notional amount of liabilities, Liabilities	1,914	1,955
Notional amount of liabilities, Net total	29,459	30,145
Correspondent interest rate swaps (financial institution counterparty):
Fair Value of liabilities, Assets	(324)	(460)
Fair Value of liabilities, Liabilities	5	4
Fair Value of liabilities, Net total	$ (319)	$ (456)

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