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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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- Definition 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 + Details
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