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Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2021 USD ($) loan | Sep. 30, 2022 USD ($) | Dec. 31, 2020 USD ($)
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 6,999,990 | $ 7,096,916 |
Non - performing | $ 66,291 | 22,777 | $ 146,774
Number of modified loans | loan | 8 |  |
Modified loans | $ 28,800 |  |
Current |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 6,927,943 | 7,067,800 |
Total Past Due Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 72,047 | 29,116 |
30-59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 3,085 | 2,910 |
60-89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,671 | 3,429 |
Commercial Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 5,406,584 | 5,239,648 |
Commercial Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,690,528 | 2,562,582 |
Non - performing | 31,488 | 7,833 | 101,070
Commercial Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,513,523 | 1,501,879 |
Non - performing | 15,239 | 335 | 16,985
Commercial Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 424,755 | 375,279 |
Non - performing | 2,471 | 384 | 384
Commercial Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,135,693 | 1,177,603 |
Non - performing | 9,641 | 6,445 | 17,122
Commercial Loans | Current | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,659,040 | 2,554,749 |
Commercial Loans | Current | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,497,755 | 1,501,512 |
Commercial Loans | Current | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 421,834 | 374,895 |
Commercial Loans | Current | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,124,748 | 1,168,727 |
Commercial Loans | Total Past Due Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 31,488 | 7,833 |
Commercial Loans | Total Past Due Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 15,768 | 367 |
Commercial Loans | Total Past Due Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,921 | 384 |
Commercial Loans | Total Past Due Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 10,945 | 8,876 |
Commercial Loans | 30-59 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial Loans | 30-59 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 529 | 29 |
Commercial Loans | 30-59 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 450 | 0 |
Commercial Loans | 30-59 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 813 | 574 |
Commercial Loans | 60-89 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial Loans | 60-89 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 3 |
Commercial Loans | 60-89 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial Loans | 60-89 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 491 | 1,857 |
Consumer Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,593,406 | 1,857,268 |
Consumer Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 357,900 |  |
Consumer Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,127,585 | 1,352,965 |
Non - performing | 7,294 | 7,373 | 11,117
Consumer Loans | Other Consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 107,906 | 126,608 |
Non - performing | 158 | 407 | $ 96
Consumer Loans | Current | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,117,074 | 1,341,890 |
Consumer Loans | Current | Other Consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 107,492 | 126,027 |
Consumer Loans | Total Past Due Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 10,511 | 11,075 |
Consumer Loans | Total Past Due Loans | Other Consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 414 | 581 |
Consumer Loans | 30-59 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,087 | 2,188 |
Consumer Loans | 30-59 Days Past Due | Other Consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 206 | 119 |
Consumer Loans | 60-89 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,130 | 1,514 |
Consumer Loans | 60-89 Days Past Due | Other Consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 50 | $ 55 |

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