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Loans and Loans Held for Sale - Narrative (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 USD ($) SecurityLoan | Mar. 31, 2021 SecurityLoan | Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Unearned income | $ 10,100 |  | $ 14,100
Purchase accounting fair value adjustments | 5,700 |  | 6,700
Total loans | 6,863,996 |  | 6,901,414
Loans held for investment, outstanding balance | $ 6,963,911 |  | 6,999,990
Threshold period of satisfactory performance for troubled debt restructuring to be restored to accruing status | 6 months |  |
Number of troubled debt restructuring loans returned to accruing status | SecurityLoan | 0 | 0 |
Number of commitments to lend additional funds on TDRs | SecurityLoan | 12 |  |
Commitments to lend additional funds on TDRs | $ 800 |  |
Commercial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | $ 5,331,863 |  | $ 5,406,584
Percentage of commercial loans in total portfolio loans | 76.60% |  | 77.20%
Commercial | CARES Act, Paycheck Protection Program Loans |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Total loans | $ 41,900 |  | $ 88,300
Business banking portfolio |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 1,100,000 |  | 1,100,000
Consumer |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 1,632,048 |  | 1,593,406
Commercial real estate | Commercial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 2,705,799 |  | 2,690,528
Commercial real estate | Business banking portfolio |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 552,200 |  | 546,100
Commercial and industrial | Commercial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 1,458,506 |  | 1,513,523
Commercial and industrial | Business banking portfolio |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 216,700 |  | 215,400
Commercial and industrial | Business banking portfolio | CARES Act, Paycheck Protection Program Loans |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 20,600 |  | 39,700
Commercial construction | Commercial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 383,237 |  | 424,755
Commercial construction | Business banking portfolio |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 15,400 |  | 16,200
Consumer real estate | Business banking portfolio |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 357,000 |  |
Consumer real estate | Consumer |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 1,162,857 |  | 1,127,585
Business banking | Commercial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | 1,141,236 |  | 1,135,693
Business banking | Consumer |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance |  |  | 357,900
CRE and commercial construction | Commercial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for investment, outstanding balance | $ 3,700,000 |  | $ 3,700,000
Combined percentage of commercial real estate and commercial construction in total commercial loans | 68.60% |  | 68.00%
Combined percentage of commercial real estate and commercial construction in total portfolio loans | 52.50% |  | 52.50%
Out of market exposure of combined portfolio | 6.10% |  | 5.70%
Percentage of total loans out-of-state excluding contiguous states | 3.20% |  | 3.00%

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