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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 ($) loan SecurityLoan | Dec. 31, 2020 USD ($) SecurityLoan loan | Dec. 31, 2019 USD ($)
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | $ 6,999,990 | $ 7,225,860 |
Non- performing | $ 66,291 | $ 146,774 | $ 54,057
CARES Act, Paycheck Protection Program Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Number of modified loans | loan | 8 | 52 |
Modified loans | $ 28,800 | $ 195,600 |
Current |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 6,927,943 | 7,069,730 |
30-59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 3,085 | 2,888 |
60-89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 2,672 | 5,965 |
90 Days + Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income |  | 503 |
Total Past Due Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | $ 72,048 | $ 156,130 |
Commercial | CARES Act, Paycheck Protection Program Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Number of modified loans | SecurityLoan | 8 | 52 |
Modified loans | $ 28,800 | $ 195,600 |
Commercial | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 2,690,528 | 2,791,947 |
Non- performing | 31,488 | 101,070 | 25,356
Commercial | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 1,513,523 | 1,559,552 |
Non- performing | 15,239 | 16,985 | 10,911
Commercial | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 424,755 | 466,077 |
Non- performing | 2,471 | 384 | 737
Commercial | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 1,135,693 | 1,160,067 |
Non- performing | 9,641 | 17,122 | 9,863
Commercial | Current | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 2,659,040 | 2,690,877 |
Commercial | Current | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 1,497,755 | 1,542,567 |
Commercial | Current | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 421,834 | 462,094 |
Commercial | Current | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 1,124,748 | 1,140,581 |
Commercial | 30-59 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 0 | 0 |
Commercial | 30-59 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 529 | 0 |
Commercial | 30-59 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 450 | 19 |
Commercial | 30-59 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 813 | 1,614 |
Commercial | 60-89 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 0 | 0 |
Commercial | 60-89 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 0 | 0 |
Commercial | 60-89 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 0 | 3,580 |
Commercial | 60-89 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 491 | 379 |
Commercial | 90 Days + Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income |  | 0 |
Commercial | 90 Days + Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income |  | 0 |
Commercial | 90 Days + Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income |  | 0 |
Commercial | 90 Days + Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income |  | 371 |
Commercial | Total Past Due Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 31,488 | 101,070 |
Commercial | Total Past Due Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 15,768 | 16,985 |
Commercial | Total Past Due Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 2,921 | 3,983 |
Commercial | Total Past Due Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 10,945 | 19,486 |
Consumer | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 1,127,585 | 1,167,332 |
Non- performing | 7,294 | 11,117 | 6,063
Consumer | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 107,906 | 80,885 |
Non- performing | 158 | 96 | $ 1,127
Consumer | Current | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 1,117,073 | 1,153,028 |
Consumer | Current | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 107,492 | 80,583 |
Consumer | 30-59 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 1,087 | 1,087 |
Consumer | 30-59 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 206 | 168 |
Consumer | 60-89 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 2,130 | 1,968 |
Consumer | 60-89 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 50 | 37 |
Consumer | 90 Days + Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income |  | 132 |
Consumer | 90 Days + Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income |  | 0 |
Consumer | Total Past Due Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | 10,512 | 14,304 |
Consumer | Total Past Due Loans | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Portfolio loans, net of unearned income | $ 414 | $ 302 |

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