Fair Value (Details 4) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Carrying amount and estimated fair value of financial instruments
Fair value	$ 9,435	$ 10,082
Securities available-for-sale	785,693	814,931
Restricted Investments	10,390	10,379
Accrued interest receivable	14,630	12,913
Deposits	(2,407,061)	(2,458,653)
Fair Value, Inputs, Level 1 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	19,029	20,682
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0
Securities available-for-sale	0	0
Loans Receivable, Fair Value Disclosure	0	0
Accrued interest receivable	0	0
Deposits	0	0
Short-term borrowings	0	0
Federal Home Loan Bank advances	0
Accrued interest payable	0	0
Fair Value, Inputs, Level 2 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	30,989	53,425
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	7,600
Securities available-for-sale	779,135	796,646
Loans Receivable, Fair Value Disclosure	0	0
Accrued interest receivable	4,070	3,596
Deposits	(2,394,553)	(2,456,900)
Short-term borrowings	(58,680)	(57,686)
Federal Home Loan Bank advances	(35,000)
Accrued interest payable	(530)	(372)
Fair Value, Inputs, Level 3 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0
Securities available-for-sale	6,558	18,285
Loans Receivable, Fair Value Disclosure	1,874,643	1,878,166
Accrued interest receivable	10,560	9,317
Deposits	0	0
Short-term borrowings	0	0
Federal Home Loan Bank advances	0
Accrued interest payable	0	0
Reported Value Measurement [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	50,018	74,107
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	7,600
Securities available-for-sale	785,693	814,931
Restricted Investments	10,390	10,379
Loans Receivable, Fair Value Disclosure	1,921,479	1,886,852
Accrued interest receivable	14,630	12,913
Deposits	(2,407,061)	(2,458,653)
Short-term borrowings	(58,680)	(57,686)
Federal Home Loan Bank advances	(35,000)
Accrued interest payable	(530)	(372)
Estimate of Fair Value Measurement [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	50,018	74,107
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	7,600
Securities available-for-sale	785,693	814,931
Loans Receivable, Fair Value Disclosure	1,874,643	1,878,166
Accrued interest receivable	14,630	12,913
Deposits	(2,394,553)	(2,456,900)
Short-term borrowings	(58,680)	(57,686)
Federal Home Loan Bank advances	(35,000)
Accrued interest payable	$ (530)	$ (372)

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

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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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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value portion of federal funds sold and securities borrowed or purchased under agreements to resell.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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Amount of interest payable on debt, including, but not limited to, trade payables.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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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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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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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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