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Loans and Allowance for Credit Losses on Loans - Troubled Debt Restructuring Modifications (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) contract	Sep. 30, 2020 USD ($) contract	Sep. 30, 2021 USD ($) contract loan	Sep. 30, 2020 USD ($) contract loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts Modified | contract			1	6
Pre-Modification Outstanding Recorded Investment			$ 1,101	$ 2,210
Post-Modification Outstanding Recorded Investment			1,101	2,202
Post-Modification Outstanding Recorded Investment at Period End			$ 1,101	$ 2,183
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			1
Pre-Modification Outstanding Recorded Investment	$ 1,101			$ 170
Post-Modification Outstanding Recorded Investment	1,101			162
Post-Modification Outstanding Recorded Investment at Period End	$ 1,101			$ 144
Commercial real estate, investor-owned | Commercial 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 | Residential loans
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 loans | Consumer loans
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				$ 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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Amount, before troubled debt restructuring, of financing receivable to be modified.

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-Name Accounting Standards Codification
-Topic 310
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