Loans and Credit Quality - Summary of Trouble Debt Restructurings that Subsequently Defaulted (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018 USD ($) contract	Dec. 31, 2017 contract
Financing Receivable, Modifications [Line Items]
TDR that subsequently defaulted, number of contracts \| contract	3	0
TDRs subsequently defaulted, recorded investment \| $	$ 1,890
AQR Substandard \| Commercial
Financing Receivable, Modifications [Line Items]
TDR that subsequently defaulted, number of contracts \| contract	2
TDRs subsequently defaulted, recorded investment \| $	$ 559
AQR Substandard \| Real estate term owner occupied
Financing Receivable, Modifications [Line Items]
TDR that subsequently defaulted, number of contracts \| contract	1
TDRs subsequently defaulted, recorded investment \| $	$ 1,331

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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