Loans and Allowance for Loan Losses - Summary of Recorded Investment in Loans Impairment Method and Activity in Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Reserves:
Loan losses, Reserves	$ 11,420	$ 11,420		$ 14,162
Loans evaluated for impairment:
Loans, Individually evaluated for impairment	3,950	3,950		6,133
Loans, Collectively evaluated for impairment	1,192,256	1,192,256		1,103,583
Total loans, gross	1,196,522	1,196,522		1,110,446
Allowance for loan losses:
Allowance for loan losses, Beginning balance	10,627	14,162	$ 10,023	10,023
Allowance for loan losses, Provisions		(3,488)	3,599	4,974
Allowance for loan losses, Charge-offs			(223)	(835)
Allowance for loan losses, Recoveries	93	746
Allowance for loan losses, Ending balance	11,420	11,420	13,399	14,162
Loans Acquired with Deteriorated Credit Quality
Loans evaluated for impairment:
Loans acquired	316	316		730
Specific Reserves
Reserves:
Loan losses, Reserves				1,782
General Reserves
Reserves:
Loan losses, Reserves	11,420	11,420		12,380
Real Estate
Reserves:
Loan losses, Reserves	7,672	7,672		8,111
Loans evaluated for impairment:
Loans, Individually evaluated for impairment	2,580	2,580		2,556
Loans, Collectively evaluated for impairment	819,654	819,654		744,349
Total loans, gross	822,550	822,550		747,635
Allowance for loan losses:
Allowance for loan losses, Beginning balance	6,433	8,111	5,788	5,788
Allowance for loan losses, Provisions				2,323
Allowance for loan losses, Ending balance	7,672	7,672	10,275	8,111
Real Estate \| Loans Acquired with Deteriorated Credit Quality
Loans evaluated for impairment:
Loans acquired	316	316		730
Real Estate \| General Reserves
Reserves:
Loan losses, Reserves	7,672	7,672		8,111
Commercial
Reserves:
Loan losses, Reserves	3,362	3,362		6,051
Loans evaluated for impairment:
Loans, Individually evaluated for impairment	1,370	1,370		3,577
Loans, Collectively evaluated for impairment	372,602	372,602		359,234
Total loans, gross	373,972	373,972		362,811
Allowance for loan losses:
Allowance for loan losses, Beginning balance	3,384	6,051	4,235	4,235
Allowance for loan losses, Provisions				2,651
Allowance for loan losses, Charge-offs			(223)	(835)
Allowance for loan losses, Recoveries	93	746
Allowance for loan losses, Ending balance	3,362	3,362	$ 3,124	6,051
Commercial \| Specific Reserves
Reserves:
Loan losses, Reserves				1,782
Commercial \| General Reserves
Reserves:
Loan losses, Reserves	3,362	3,362		$ 4,269
Unallocated
Reserves:
Loan losses, Reserves	386	386
Allowance for loan losses:
Allowance for loan losses, Beginning balance	810
Allowance for loan losses, Ending balance	386	386
Unallocated \| General Reserves
Reserves:
Loan losses, Reserves	$ 386	$ 386

Allowance for loan and lease losses reserves.

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Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The balance of financing receivables that were collectively evaluated for impairment.

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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.

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Amount before allowance and after 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.

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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