Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Minimum future rental commitments under noncancellable operating leases [Abstract]
2019	$ 782
2020	743
2021	555
2022	231
2023	173
Due remaining term of the lease	493
Commitments to Extend Credit [Member]
Off Balance Sheet Commitments [Abstract]
Off-balance sheet risks, amount, liability	828,539	$ 735,678
Letters of Credit [Member]
Off Balance Sheet Commitments [Abstract]
Off-balance sheet risks, amount, liability	$ 19,108	20,061
Letters of Credit [Member] \| Minimum [Member]
Off Balance Sheet Commitments [Abstract]
Off balance sheet risks maturity period	1 month
Letters of Credit [Member] \| Maximum [Member]
Off Balance Sheet Commitments [Abstract]
Off balance sheet risks maturity period	37 months
Performance Guarantees under Interest Rate Swap Contracts Entered into between our Borrowing Customers and Third Parties [Member]
Off Balance Sheet Commitments [Abstract]
Off-balance sheet risks, amount, liability	$ 0	$ 759

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Maturity period of letters of credit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The fair value 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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