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Loans and Loans Held for Sale - Narrative (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 USD ($) loan SecurityLoan | Dec. 31, 2020 USD ($) loan SecurityLoan
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Unearned income | $ 14,100 | $ 16,000
Purchase accounting fair value adjustments | 6,700 | 8,600
Financing receivable, excluding accrued interest, after allowance for credit loss | 6,901,414 | 7,108,248
Portfolio loans, net of unearned income | 6,999,990 | 7,225,860
Portfolio loans, net of unearned income | $ 6,999,990 | $ 7,225,860
Number of commitments to lend additional funds | loan | 12 | 20
Commitment to lend additional funds | $ 2,600 | $ 800
Number of TDRs returned back to accruing status | loan | 0 | 1
Financial receivable trouble debt restructuring reclassified to accruing trouble debt restructuring status |  | $ 100
Minimum period of loan payment defaults following restructure for TDRs to be in default (in days) | 90 days |
Number of TDRs defaulted that were restructured within the last 12 months prior to defaulting | loan | 0 | 6
Financial receivable defaulted trouble debt restructuring loans restructured within twelve months prior to defaulting |  | $ 11,800
CARES Act, Paycheck Protection Program Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of modified loans | loan | 8 | 52
Modified loans | $ 28,800 | $ 195,600
Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | $ 5,406,584 | $ 5,673,707
Percentage of commercial loans in total portfolio loans | 77.20% | 78.50%
Commercial | CARES Act, Paycheck Protection Program Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing receivable, excluding accrued interest, after allowance for credit loss |  | $ 465,000
Number of modified loans | SecurityLoan | 8 | 52
Modified loans | $ 28,800 | $ 195,600
Business Banking Portfolio Segment |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 1,100,000 | 1,200,000
Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 1,593,406 | 1,552,153
CARES Act, Paycheck Protection Program Loans | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Financing receivable, after allowance for credit loss | 88,300 |
Commercial real estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 2,690,528 | 2,791,947
Commercial real estate | Business Banking Portfolio Segment |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 546,100 | 453,000
Commercial and industrial | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 1,513,523 | 1,559,552
Commercial and industrial | Business Banking Portfolio Segment |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 215,400 | 394,900
Commercial and industrial | Business Banking Portfolio Segment | CARES Act, Paycheck Protection Program Loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 39,700 | 178,400
Commercial construction | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 424,755 | 466,077
Commercial construction | Business Banking Portfolio Segment |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 16,200 | 8,200
Consumer real estate | Business Banking Portfolio Segment |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 357,900 |
Consumer real estate | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 1,127,585 | 1,167,332
Business banking | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | 1,135,693 | 1,160,067
Business banking | Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income |  | 303,900
CRE and Commercial Construction | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Portfolio loans, net of unearned income | $ 3,700,000 | $ 3,700,000
Combined percentage of commercial real estate and commercial construction in total commercial loans | 68.00% | 65.60%
Combined percentage of commercial real estate and commercial construction in total portfolio loans | 52.50% | 51.50%
Out-of-state exposure of combined portfolio | 5.70% | 5.90%
Percentage of total loans out-of-state excluding contiguous states | 3.00% | 3.00%

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