Loans and The Allowance for Loan Losses - Summary of Average Recorded Investments and Interest Income of Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 11,216	$ 11,113
Interest Income Recognized	117	104
Consumer, Excluding Consumer Other Portfolio Segment \| 1-4 Family Residential
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	5,988	6,620
Interest Income Recognized	78	78
Consumer, Excluding Consumer Other Portfolio Segment \| Home Equity
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,357	1,087
Interest Income Recognized	9	14
Consumer, Excluding Consumer Other Portfolio Segment \| Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	3,571	3,007
Interest Income Recognized	24	8
Consumer
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	147	167
Interest Income Recognized	2	1
Commercial business
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	153	232
Interest Income Recognized	$ 4	$ 3

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Average 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 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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