Loans, Net - Consolidated loan portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Loan Portfolio [Abstract]
Outstanding Balance, Gross	$ 780,867	$ 754,846
Less allowance for loan losses	11,400	11,786	$ 13,320
Net loans	$ 769,467	$ 743,060
Percent of Total Portfolio	100.00%	100.00%
Net of deferred loan costs	$ 3,300	$ 3,000
Construction [Member]
Consolidated Loan Portfolio [Abstract]
Outstanding Balance, Gross	33,381	33,050
Less allowance for loan losses	$ 780	$ 550	847
Percent of Total Portfolio	4.30%	4.40%
Secured by farmland [Member]
Consolidated Loan Portfolio [Abstract]
Outstanding Balance, Gross	$ 19,391	$ 19,708
Percent of Total Portfolio	2.50%	2.60%
Secured by 1-4 family residential [Member]
Consolidated Loan Portfolio [Abstract]
Outstanding Balance, Gross	$ 273,176	$ 265,216
Less allowance for loan losses	$ 3,835	$ 3,966	6,734
Percent of Total Portfolio	35.00%	35.10%
Other real estate loans [Member]
Consolidated Loan Portfolio [Abstract]
Outstanding Balance, Gross	$ 258,012	$ 255,236
Less allowance for loan losses	$ 3,730	$ 3,916	3,506
Percent of Total Portfolio	33.00%	33.80%
Commercial loans [Member]
Consolidated Loan Portfolio [Abstract]
Outstanding Balance, Gross	$ 179,907	$ 163,269
Less allowance for loan losses	$ 1,691	$ 2,354	1,890
Percent of Total Portfolio	23.00%	21.60%
Consumer loans [Member]
Consolidated Loan Portfolio [Abstract]
Outstanding Balance, Gross	$ 17,000	$ 18,367
Less allowance for loan losses	$ 1,173	$ 821	$ 177
Percent of Total Portfolio	2.20%	2.50%

The percentage of total loan portfolio during the period.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

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