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Allowance for Credit Losses - Summary of Allowance for Credit Losses and Recorded Investments (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Jan. 01, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for Loan Losses, Individually Evaluated for Impairment |  |  | $ 2,200 |
Allowance for Loan Losses, Collectively Evaluated for Impairment |  |  | 60,024 |
Total | $ 117,612 | $ 62,224 | 62,224 | $ 60,996
Portfolio Loans, Individually Evaluated for Impairment |  |  | 75,337 |
Portfolio Loans, Collectively Evaluated for Impairment |  |  | 7,061,815 |
Total | 7,225,860 |  | 7,137,152 |
Commercial |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Total | 5,977,643 |  | 5,756,971 |
Consumer |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Total | $ 1,248,217 |  | 1,380,181 |
Commercial real estate | Commercial |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for Loan Losses, Individually Evaluated for Impairment |  |  | 2,023 |
Allowance for Loan Losses, Collectively Evaluated for Impairment |  |  | 28,554 |
Total |  |  | 30,577 |
Portfolio Loans, Individually Evaluated for Impairment |  |  | 47,920 |
Portfolio Loans, Collectively Evaluated for Impairment |  |  | 3,368,598 |
Total |  |  | 3,416,518 |
Commercial and industrial | Commercial |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for Loan Losses, Individually Evaluated for Impairment |  |  | 55 |
Allowance for Loan Losses, Collectively Evaluated for Impairment |  |  | 15,626 |
Total |  |  | 15,681 |
Portfolio Loans, Individually Evaluated for Impairment |  |  | 17,606 |
Portfolio Loans, Collectively Evaluated for Impairment |  |  | 1,703,227 |
Total |  |  | 1,720,833 |
Commercial construction | Commercial |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for Loan Losses, Individually Evaluated for Impairment |  |  | 113 |
Allowance for Loan Losses, Collectively Evaluated for Impairment |  |  | 7,787 |
Total |  |  | 7,900 |
Portfolio Loans, Individually Evaluated for Impairment |  |  | 1,914 |
Portfolio Loans, Collectively Evaluated for Impairment |  |  | 373,531 |
Total |  |  | 375,445 |
Consumer real estate | Consumer |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for Loan Losses, Individually Evaluated for Impairment |  |  | 0 |
Allowance for Loan Losses, Collectively Evaluated for Impairment |  |  | 6,337 |
Total |  |  | 6,337 |
Portfolio Loans, Individually Evaluated for Impairment |  |  | 7,884 |
Portfolio Loans, Collectively Evaluated for Impairment |  |  | 1,537,439 |
Total |  |  | 1,545,323 |
Other consumer | Consumer |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for Loan Losses, Individually Evaluated for Impairment |  |  | 9 |
Allowance for Loan Losses, Collectively Evaluated for Impairment |  |  | 1,720 |
Total |  |  | 1,729 |
Portfolio Loans, Individually Evaluated for Impairment |  |  | 13 |
Portfolio Loans, Collectively Evaluated for Impairment |  |  | 79,020 |
Total |  |  | $ 79,033 |

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- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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