Loans, Allowance for Loan Losses and Credit Quality - Summary of Average Recorded Investment and Interest Income recognized on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	$ 5,943	$ 5,686
Impaired loans, Ending Recorded Investment	5,810	5,393	$ 7,531
Impaired loans, Interest Income	50	36
Equity Lines of Credit
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	50	100
Impaired loans, Ending Recorded Investment		100	200
Impaired loans, Interest Income	1	1
Commercial Loans
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	577	1,605
Impaired loans, Ending Recorded Investment	650	1,735	685
Impaired loans, Interest Income	6	7
Consumer Loans
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	19
Impaired loans, Ending Recorded Investment	37		39
Mortgage Loans on Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	5,297	3,981
Impaired loans, Ending Recorded Investment	5,123	3,558	6,607
Impaired loans, Interest Income	43	28
Mortgage Loans on Real Estate \| Residential Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	1,720	1,194
Impaired loans, Ending Recorded Investment	2,326	1,233	1,201
Impaired loans, Interest Income	18	18
Mortgage Loans on Real Estate \| Commercial Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	3,562	2,697
Impaired loans, Ending Recorded Investment	2,797	2,232	5,375
Impaired loans, Interest Income	25	9
Mortgage Loans on Real Estate \| Construction and Land Development
Financing Receivable Impaired [Line Items]
Impaired loans, Average Recorded Investment	$ 15	90
Impaired loans, Ending Recorded Investment		93	$ 31
Impaired loans, Interest Income		$ 1

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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=66008989&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=66008989&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.

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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=66008989&loc=SL6953550-111524

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