Loans and Credit Quality - Summary of Trouble Debt Restructurings that Subsequently Defaulted (Details) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR that subsequently defaulted, number of contracts \| contract	0	3
TDRs subsequently defaulted, recorded investment \| $	$ 0	$ 1,890
AQR Substandard \| Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR that subsequently defaulted, number of contracts \| contract	0	2
TDRs subsequently defaulted, recorded investment \| $	$ 0	$ 559
AQR Substandard \| Real estate term owner occupied
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR that subsequently defaulted, number of contracts \| contract	0	1
TDRs subsequently defaulted, recorded investment \| $	$ 0	$ 1,331

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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