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Allowance for Credit Losses - Collateral Dependent Loans by Class of Loan (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | $ 7,096,916 | $ 6,999,990
Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 8,611 | 34,456
Business Assets |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,833 | 6,541
Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 480 | 0
Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 10,473
Commercial Loans |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 5,239,648 | 5,406,584
Commercial Loans | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 2,562,582 | 2,690,528
Commercial Loans | Commercial real estate | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 5,837 | 28,046
Commercial Loans | Commercial real estate | Business Assets |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial Loans | Commercial real estate | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 480 | 0
Commercial Loans | Commercial real estate | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,501,879 | 1,513,523
Commercial Loans | Commercial and industrial | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 259
Commercial Loans | Commercial and industrial | Business Assets |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 658 | 4,905
Commercial Loans | Commercial and industrial | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial Loans | Commercial and industrial | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 10,473
Commercial Loans | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 375,279 | 424,755
Commercial Loans | Commercial construction | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,674 | 4,210
Commercial Loans | Commercial construction | Business Assets |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial Loans | Commercial construction | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial Loans | Commercial construction | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,177,603 | 1,135,693
Commercial Loans | Business banking | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 524 | 910
Commercial Loans | Business banking | Business Assets |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,175 | 1,636
Commercial Loans | Business banking | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Commercial Loans | Business banking | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Consumer Loans |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,857,268 | 1,593,406
Consumer Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance |  | 357,900
Consumer Loans | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 1,352,965 | 1,127,585
Consumer Loans | Consumer real estate | Real Estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 576 | 1,031
Consumer Loans | Consumer real estate | Business Assets |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Consumer Loans | Consumer real estate | Investment/Cash |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | 0 | 0
Consumer Loans | Consumer real estate | Other |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Loans held for investment, outstanding balance | $ 0 | $ 0

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