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Loans and Allowance for Credit Losses on Loans - Troubled Debt Restructuring Narrative (Details) $ in Millions | 1 Months Ended | 3 Months Ended
--- | --- | ---
Aug. 12, 2021 USD ($) borrowingRelationship loan | Jun. 30, 2021 USD ($) borrowingRelationship loan | Jun. 30, 2020 loan
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
Number of loans removed from TDR designation |  | 0 | 0
Financing receivable, loan modifications under CARES Act, payment relief, number of borrowing relationships | borrowingRelationship |  | 7 |
Financing receivable, loan modifications under CARES Act, payment relief |  | 12 |
Financing receivable, modified under CARES Act, payment relief | $ |  | $ 49.8 |
Financing receivable, weighted average loan-to-value ratio, modified under CARES Act, remaining payment relief |  | 41.00% |
Subsequent event |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |
Financing receivable, loan modifications under CARES Act during period, borrowing relationships, subsequently resumed payments | borrowingRelationship | 1 |  |
Financing receivable, loan modifications under CARES Act during period, subsequently resumed payments | 3 |  |
Financing receivable, modified under CARES Act during period, subsequently resumed payments | $ | $ 6.4 |  |

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