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Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Class (Details)	3 Months Ended
	Mar. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans removed from TDR designation | loan	0
Recorded investment of loans removed from TDR resignation	$ 150,000
Recorded investment in Troubled Debt Restructurings	14,088,000	$ 14,406,000
TDR loans acquired	$ 0	0
TDR loans on non-accrual status, quantity | loan	2
TDR loans on non-accrual status	$ 64,000	65,000
Commercial loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	1,198,000	1,506,000
Commercial real estate loans | Commercial real estate, owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	7,001,000	6,993,000
Commercial real estate loans | Commercial real estate, investor
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	1,812,000	1,821,000
Commercial real estate loans | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	2,691,000	2,688,000
Residential loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	$ 251,000	251,000
Residential loans | Other residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans removed from TDR designation | loan	1
Recorded investment in Troubled Debt Restructurings	$ 460,000	462,000
Consumer loans | Installment and other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	$ 675,000	$ 685,000

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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