Fair Value (Details 4) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Carrying amount and estimated fair value of financial instruments
Fair value	$ 7,371	$ 8,600
Securities available-for-sale	851,577	853,725
Restricted Investments	10,369	10,359
Accrued interest receivable	11,564	12,311
Deposits	(2,427,723)	(2,428,526)
Fair Value, Inputs, Level 1 [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	18,860	21,047
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0	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	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	36,519	53,965
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0	6,952
Securities available-for-sale	835,614	837,147
Loans Receivable, Fair Value Disclosure	0	0
Accrued interest receivable	3,522	3,340
Deposits	(2,427,396)	(2,414,555)
Short-term borrowings	(51,880)	(80,989)
Federal Home Loan Bank advances	(136)	(137)
Accrued interest payable	(327)	(363)
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	0
Securities available-for-sale	15,963	16,578
Loans Receivable, Fair Value Disclosure	1,851,920	1,854,046
Accrued interest receivable	8,042	8,971
Deposits	0	0
Short-term borrowings	0	0
Federal Home Loan Bank advances	0	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	55,379	75,012
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0	6,952
Securities available-for-sale	851,577	853,725
Restricted Investments	10,369	10,359
Loans Receivable, Fair Value Disclosure	1,837,350	1,820,407
Accrued interest receivable	11,564	12,311
Deposits	(2,427,723)	(2,428,526)
Short-term borrowings	(51,880)	(80,989)
Federal Home Loan Bank advances	(132)	(132)
Accrued interest payable	(327)	(363)
Estimate of Fair Value Measurement [Member]
Carrying amount and estimated fair value of financial instruments
Cash and Cash Equivalents, Fair Value Disclosure	55,379	75,012
Federal Funds Sold and Securities Borrowed or Purchased under Agreements to Resell, Fair Value Disclosure	0	6,952
Securities available-for-sale	851,577	853,725
Loans Receivable, Fair Value Disclosure	1,851,920	1,854,046
Accrued interest receivable	11,564	12,311
Deposits	(2,427,396)	(2,414,555)
Short-term borrowings	(51,880)	(80,989)
Federal Home Loan Bank advances	(136)	(137)
Accrued interest payable	$ (327)	$ (363)

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-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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