Fair Value Measurements - Schedule of Valuation Process Used to Determine Fair Value Measurement within Level 3 (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Fair value valuation processes
Investment securities available for sale	$ 177,591	$ 132,981
OREO recorded at fair value	5,351	5,351
Impaired Loans
Fair value valuation processes
Impaired loans	2,969	1,425
OREO
Fair value valuation processes
OREO recorded at fair value	5,351	5,351
Market approach \| Trust preferred securities
Fair value valuation processes
Investment securities available for sale	$ 9,167	$ 9,448
Valuation technique	Market approach	Market approach
Unobservable input	Discount to carrying value using broker quotes or observable prices on similar securities	Discount to carrying value using broker quotes or observable prices on similar securities
Market approach \| Weighted average \| Trust preferred securities
Fair value valuation processes
Discount rate	7.00%	13.00%
Market approach \| Minimum \| Trust preferred securities
Fair value valuation processes
Discount rate	5.00%	1.00%
Market approach \| Maximum \| Trust preferred securities
Fair value valuation processes
Discount rate	13.00%	28.00%
Commercial \| Sales comparison \| Impaired Loans
Fair value valuation processes
Impaired loans	$ 2,509	$ 1,057
Valuation technique	Sales comparison (1)	Sales comparison (1)
Unobservable input	Management discount for asset type	Management discount for asset type
Commercial \| Sales comparison \| Weighted average \| Impaired Loans
Fair value valuation processes
Discount rate	53.00%	59.00%
Commercial \| Sales comparison \| Minimum \| Impaired Loans
Fair value valuation processes
Discount rate	0.00%	76.00%
Commercial \| Sales comparison \| Maximum \| Impaired Loans
Fair value valuation processes
Discount rate	90.00%	0.00%
Commercial \| Property appraisals \| OREO
Fair value valuation processes
OREO recorded at fair value	$ 190	$ 190
Valuation technique	Property appraisals (2)	Property appraisals (2)
Unobservable input	Management discount for property type	Management discount for property type
Discount rate		0.00%
Commercial \| Property appraisals \| Weighted average \| OREO
Fair value valuation processes
Discount rate	0.00%	0.00%
Real estate - mortgage \| Maximum \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments	(4.00%)
Real estate - mortgage \| Sales comparison \| Impaired Loans
Fair value valuation processes
Impaired loans	$ 303	$ 269
Valuation technique	Sales comparison (2)	Sales comparison (2)
Unobservable input	Sales comparison adjustments	Sales comparison adjustments
Real estate - mortgage \| Sales comparison \| Weighted average \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments	(2.00%)	18.00%
Real estate - mortgage \| Sales comparison \| Minimum \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments	(1.00%)
Construction and land \| Property appraisals \| OREO
Fair value valuation processes
OREO recorded at fair value	$ 5,161	$ 5,161
Valuation technique	Property appraisals (2)	Property appraisals (2)
Unobservable input	Management discount for property type	Management discount for property type
Construction and land \| Property appraisals \| Weighted average \| OREO
Fair value valuation processes
Discount rate	17.00%	17.00%
Consumer \| Sales comparison \| Impaired Loans
Fair value valuation processes
Impaired loans	$ 157	$ 99
Valuation technique	Sales comparison (2)	Sales comparison (2)
Unobservable input	Sales comparison adjustments	Sales comparison adjustments
Consumer \| Sales comparison \| Weighted average \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments	(36.00%)	(1.00%)
Consumer \| Sales comparison \| Minimum \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments		(11.00%)
Consumer \| Sales comparison \| Maximum \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments		10.00%
Consumer \| Property appraisals \| Minimum \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments	(13.00%)
Consumer \| Property appraisals \| Maximum \| Impaired Loans
Fair value valuation processes
Sales comparison adjustments	(59.00%)

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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