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Summary of Significant Accounting Policies (Adoption Impact of ASU 2016-13) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Jan. 01, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | --- | --- | ---
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance | $ 220,834 |  | $ 160,682 | $ 159,932 | $ 159,532
Financing Receivable, Allowance for Credit Loss | 220,834 | $ 139,643 |  |  |
Off-Balance Sheet, Credit Loss, Liability | 38,307 | 17,165 | 1,075 |  |
Loans and Leases Receivable and Liability for Unfunded Lending Commitments, Allowance |  |  | 161,757 |  |
Financing Receivable, Allowance for Credit Losses and Liability for Unfunded Lending Commitments |  | 156,808 |  |  |
Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | (21,039) |  |  |
Off-Balance Sheet, Credit Loss, Liability |  | 16,090 |  |  |
Financing Receivable, Allowance for Credit Losses and Liability for Unfunded Lending Commitments |  | (4,949) |  |  |
Commercial Portfolio Segment [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 91,760 | 92,869 | 93,704
Financing Receivable, Allowance for Credit Loss | 121,549 | 62,049 |  |  |
Off-Balance Sheet, Credit Loss, Liability | 37,259 | 16,456 |  |  |
Commercial Portfolio Segment [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | (29,711) |  |  |
Commercial Portfolio Segment [Member] | Business [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 44,268 |  |
Financing Receivable, Allowance for Credit Loss |  | 37,940 |  |  |
Commercial Portfolio Segment [Member] | Business [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | (6,328) |  |  |
Commercial Portfolio Segment [Member] | Real Estate - Construction And Land [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 21,589 |  |
Financing Receivable, Allowance for Credit Loss |  | 9,204 |  |  |
Commercial Portfolio Segment [Member] | Real Estate - Construction And Land [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | (12,385) |  |  |
Commercial Portfolio Segment [Member] | Real Estate - Business [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 25,903 |  |
Financing Receivable, Allowance for Credit Loss |  | 14,905 |  |  |
Commercial Portfolio Segment [Member] | Real Estate - Business [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | (10,998) |  |  |
Personal Banking Portfolio Segment [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 68,922 | $ 67,063 | $ 65,828
Financing Receivable, Allowance for Credit Loss | 99,285 | 77,594 |  |  |
Off-Balance Sheet, Credit Loss, Liability | $ 1,048 | 709 |  |  |
Personal Banking Portfolio Segment [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 8,672 |  |  |
Personal Banking Portfolio Segment [Member] | Real Estate - Personal [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 3,125 |  |
Financing Receivable, Allowance for Credit Loss |  | 4,855 |  |  |
Personal Banking Portfolio Segment [Member] | Real Estate - Personal [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 1,730 |  |  |
Personal Banking Portfolio Segment [Member] | Consumer Loan [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 15,932 |  |
Financing Receivable, Allowance for Credit Loss |  | 14,518 |  |  |
Personal Banking Portfolio Segment [Member] | Consumer Loan [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | (1,414) |  |  |
Personal Banking Portfolio Segment [Member] | Revolving Home Equity [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 638 |  |
Financing Receivable, Allowance for Credit Loss |  | 1,624 |  |  |
Personal Banking Portfolio Segment [Member] | Revolving Home Equity [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 986 |  |  |
Personal Banking Portfolio Segment [Member] | Consumer Credit Card [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | 47,997 |  |
Financing Receivable, Allowance for Credit Loss |  | 56,495 |  |  |
Personal Banking Portfolio Segment [Member] | Consumer Credit Card [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 8,498 |  |  |
Personal Banking Portfolio Segment [Member] | Overdrafts [Member] |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Loans and Leases Receivable, Allowance |  |  | $ 1,230 |  |
Financing Receivable, Allowance for Credit Loss |  | 102 |  |  |
Personal Banking Portfolio Segment [Member] | Overdrafts [Member] | Accounting Standards Update 2016-13 |  |  |  |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | $ (1,128) |  |  |

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