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Allowance for Credit Losses - Collateral Dependent Loans by Class of Loan (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | $ 6,999,990 | $ 7,225,860
Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 34,456 | 108,525
Blanket Lien |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 6,541 | 16,699
Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 10,473 | 689
Commercial | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 2,690,528 | 2,791,947
Commercial | Commercial real estate | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 28,046 | 100,450
Commercial | Commercial real estate | Blanket Lien |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Commercial real estate | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Commercial real estate | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,513,523 | 1,559,552
Commercial | Commercial and industrial | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 259 | 1,040
Commercial | Commercial and industrial | Blanket Lien |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 4,905 | 15,080
Commercial | Commercial and industrial | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Commercial and industrial | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 10,473 | 0
Commercial | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 424,755 | 466,077
Commercial | Commercial construction | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 4,210 | 3,552
Commercial | Commercial construction | Blanket Lien |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Commercial construction | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Commercial construction | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,135,693 | 1,160,067
Commercial | Business banking | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 910 | 3,085
Commercial | Business banking | Blanket Lien |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,636 | 1,619
Commercial | Business banking | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial | Business banking | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 689
Consumer | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,127,585 | 1,167,332
Consumer | Consumer real estate | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,031 | 398
Consumer | Consumer real estate | Blanket Lien |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Consumer | Consumer real estate | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Consumer | Consumer real estate | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | $ 0 | $ 0

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