Fair Value Measurements - Schedule of Carrying Amount, Fair Value and Placement in Fair Value Hierarchy (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Financial assets:
Interest-bearing deposits in banks	$ 45,551	$ 15,137	$ 31,609
Equity securities with readily determinable fair values	1,743	0	0
Debt securities available for sale	162,957	159,051	158,392
Investment securities held to maturity	32,767	44,549	47,373
Restricted investment in bank stocks	4,529	4,773	$ 4,821
Level 1
Financial assets:
Cash and due from banks	7,981	8,313
Interest-bearing deposits in banks	45,551	15,137
Equity securities with readily determinable fair values	1,743
Debt securities available for sale	0	1,784
Investment securities held to maturity	0	0
Loans held for sale	0	0
Loans, less allowance for loan losses	0	0
Accrued interest receivable	0	0
Restricted investment in bank stocks	0	0
Financial liabilities:
Demand deposits and savings	0	0
Time deposits	0	0
Short-term borrowings	0	0
Long-term borrowings	0	0
Trust preferred subordinated debt	0	0
Accrued interest payable	0	0
Off-balance sheet financial instruments	0	0
Level 2
Financial assets:
Cash and due from banks	10,164	10,991
Interest-bearing deposits in banks	0	0
Equity securities with readily determinable fair values	0
Debt securities available for sale	162,957	157,267
Investment securities held to maturity	32,767	44,549
Loans held for sale	1,112	1,736
Loans, less allowance for loan losses	0	0
Accrued interest receivable	4,737	3,670
Restricted investment in bank stocks	4,529	4,773
Financial liabilities:
Demand deposits and savings	984,704	944,399
Time deposits	357,603	351,057
Short-term borrowings	38,525	36,908
Long-term borrowings	79,383	89,571
Trust preferred subordinated debt	4,699	4,692
Accrued interest payable	1,406	1,163
Off-balance sheet financial instruments	0	0
Level 3
Financial assets:
Cash and due from banks	0	0
Interest-bearing deposits in banks	0	0
Equity securities with readily determinable fair values	0
Debt securities available for sale	0	0
Investment securities held to maturity	0	0
Loans held for sale	0	0
Loans, less allowance for loan losses	1,218,667	1,213,932
Accrued interest receivable	0	0
Restricted investment in bank stocks	0	0
Financial liabilities:
Demand deposits and savings	0	0
Time deposits	0	0
Short-term borrowings	0	0
Long-term borrowings	0	0
Trust preferred subordinated debt	0	0
Accrued interest payable	0	0
Off-balance sheet financial instruments	0	0
Carrying Amount
Financial assets:
Cash and due from banks	18,145	19,304
Interest-bearing deposits in banks	45,551	15,137
Equity securities with readily determinable fair values	1,743
Debt securities available for sale	162,957	159,051
Investment securities held to maturity	33,517	44,829
Loans held for sale	1,112	1,736
Loans, less allowance for loan losses	1,259,032	1,230,194
Accrued interest receivable	4,737	3,670
Restricted investment in bank stocks	4,529	4,773
Financial liabilities:
Demand deposits and savings	984,704	944,399
Time deposits	362,539	354,093
Short-term borrowings	38,525	36,908
Long-term borrowings	79,725	89,600
Trust preferred subordinated debt	5,000	5,000
Accrued interest payable	1,406	1,163
Off-balance sheet financial instruments	0	0
Fair Value
Financial assets:
Cash and due from banks	18,145	19,304
Interest-bearing deposits in banks	45,551	15,137
Equity securities with readily determinable fair values	1,743
Debt securities available for sale	162,957	159,051
Investment securities held to maturity	32,767	44,549
Loans held for sale	1,112	1,736
Loans, less allowance for loan losses	1,218,667	1,213,932
Accrued interest receivable	4,737	3,670
Restricted investment in bank stocks	4,529	4,773
Financial liabilities:
Demand deposits and savings	984,704	944,399
Time deposits	357,603	351,057
Short-term borrowings	38,525	36,908
Long-term borrowings	79,383	89,571
Trust preferred subordinated debt	4,699	4,692
Accrued interest payable	1,406	1,163
Off-balance sheet financial instruments	$ 0	$ 0

Demand Deposits and Savings, Fair Value Disclosure

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Equity interest in bank stocks. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Time Deposits, Fair Value Disclosure

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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The face amount of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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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.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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