Disclosures About Fair Value of Financial Instruments - Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financial assets:
Available-for-sale securities	$ 204,880	$ 187,565
Level 1 [Member]
Financial assets:
Available-for-sale securities	80,140	27,035
Level 2 [Member]
Financial assets:
Available-for-sale securities	124,740	160,530
Recurring [Member]
Financial assets:
Available-for-sale securities	204,880	187,565
Recurring [Member] | Interest Rate Swap [Member]
Financial assets:
Customer interest rate swaps	295	274
Financial Liabilities:
Correspondent interest rate swaps	305	287
Recurring [Member] | Level 1 [Member]
Financial assets:
Available-for-sale securities	80,140	27,035
Recurring [Member] | Level 2 [Member]
Financial assets:
Available-for-sale securities	124,740	160,530
Recurring [Member] | Level 2 [Member] | Interest Rate Swap [Member]
Financial assets:
Customer interest rate swaps	295	274
Financial Liabilities:
Correspondent interest rate swaps	$ 305	$ 287