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Loans and Allowance for Credit Losses on Loans - Troubled Debt Restructuring Modifications (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($) contract	Jun. 30, 2020 USD ($) contract	Jun. 30, 2021 USD ($) contract loan	Jun. 30, 2020 USD ($) contract loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract	0	2	0	5
Pre-Modification Outstanding Recorded Investment	$ 0	$ 384	$ 0	$ 657
Post-Modification Outstanding Recorded Investment	0	384	0	649
Post-Modification Outstanding Recorded Investment at Period End	$ 0	$ 384	$ 0	$ 630
Number of modified TDR loans that defaulted | loan			0	0
Commercial and industrial | Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract				1
Pre-Modification Outstanding Recorded Investment				$ 170
Post-Modification Outstanding Recorded Investment				162
Post-Modification Outstanding Recorded Investment at Period End				$ 144
Home equity | Residential loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract		1		1
Pre-Modification Outstanding Recorded Investment		$ 276		$ 276
Post-Modification Outstanding Recorded Investment		276		276
Post-Modification Outstanding Recorded Investment at Period End		$ 276		$ 276
Installment and other consumer loans | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract		1		3
Pre-Modification Outstanding Recorded Investment		$ 108		$ 211
Post-Modification Outstanding Recorded Investment		108		211
Post-Modification Outstanding Recorded Investment at Period End		$ 108		$ 210

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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=123577603&loc=SL6953676-111524

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

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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 33
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Amount, before troubled debt restructuring, of financing receivable to be modified.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Amount of increase (decrease) in financing receivable modified from troubled debt restructuring.

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-Publisher FASB
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-SubTopic 10
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