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Loans and Allowance for Loan Losses - Troubled Debt Restructuring Modifications (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) contract	Sep. 30, 2019 USD ($) contract	Sep. 30, 2020 USD ($) contract loan	Sep. 30, 2019 USD ($) loan contract
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract		0	6
Pre-Modification Outstanding Recorded Investment		$ 0	$ 2,210
Post-Modification Outstanding Recorded Investment		0	2,202
Post-Modification Outstanding Recorded Investment at Period End		$ 0	$ 2,163
Number of modified TDR loans that defaulted | loan			0	0
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract			1	1
Pre-Modification Outstanding Recorded Investment			$ 170	$ 298
Post-Modification Outstanding Recorded Investment			162	298
Post-Modification Outstanding Recorded Investment at Period End			$ 125	$ 173
Commercial real estate, investor-owned | Commercial real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract	1		1
Pre-Modification Outstanding Recorded Investment	$ 1,553		$ 1,553
Post-Modification Outstanding Recorded Investment	1,553		1,553
Post-Modification Outstanding Recorded Investment at Period End	$ 1,553		$ 1,553
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract			1
Pre-Modification Outstanding Recorded Investment			$ 276
Post-Modification Outstanding Recorded Investment			276
Post-Modification Outstanding Recorded Investment at Period End			$ 276
Installment and other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract			3
Pre-Modification Outstanding Recorded Investment			$ 211
Post-Modification Outstanding Recorded Investment			211
Post-Modification Outstanding Recorded Investment at Period End			$ 209

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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

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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=121611835&loc=SL6953682-111524

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Amount of increase (decrease) in financing receivable modified from troubled debt restructuring.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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