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Loans, Allowance for Credit Losses and Credit Quality Financing Receivable Past Due (Details) $ in Thousands | Mar. 31, 2022 USD ($) loan | Dec. 31, 2021 USD ($) loan | Mar. 31, 2021 USD ($)
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Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan |  | 428 |  | 518 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing |  | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross |  | $ 13,580,027 | [1] | $ 13,587,286 | $ 9,246,691 |
Number Of Financing Receivables Total Past Due | loan |  | 574 |  | 701 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan |  | 38 |  | 60 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan |  | 108 |  | 123 |  |
Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 13,748 |  | $ 37,927 |  |
Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 13,086 |  | 1,677 |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 12,402 |  | 7,092 |  |
Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 13,540,791 |  | 13,540,590 |  |
Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 39,236 |  | $ 46,696 |  |
Commercial And Industrial [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan |  | 4 |  | 7 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing |  | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross |  | $ 1,566,192 | [1] | $ 1,563,279 | 2,086,671 | [1]
Number Of Financing Receivables Total Past Due | loan |  | 8 |  | 11 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan |  | 4 |  | 2 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan |  | 0 |  | 2 |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 1,566,192 |  | $ 1,563,279 |  |
Commercial And Industrial [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 276 |  | 143 |  |
Commercial And Industrial [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 3,399 |  | 252 |  |
Commercial And Industrial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 |  | 24 |  |
Commercial And Industrial [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,562,517 |  | 1,562,860 |  |
Commercial And Industrial [Member] | Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 3,675 |  | $ 419 |  |
Commercial Real Estate [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan |  | 10 |  | 15 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing |  | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross |  | $ 7,897,616 | [1] | $ 7,992,344 | 4,177,617 | [1]
Number Of Financing Receivables Total Past Due | loan |  | 15 |  | 19 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan |  | 3 |  | 0 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan |  | 2 |  | 4 |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 7,897,616 |  | $ 7,992,344 |  |
Commercial Real Estate [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 6,530 |  | 32,845 |  |
Commercial Real Estate [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 7,897 |  | 0 |  |
Commercial Real Estate [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 7,009 |  | 1,339 |  |
Commercial Real Estate [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 7,876,180 |  | 7,958,160 |  |
Commercial Real Estate [Member] | Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 21,436 |  | $ 34,184 |  |
Construction Loans [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan |  | 3 |  | 0 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing |  | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross |  | $ 1,153,945 | [1] | $ 1,165,457 | 516,362 | [1]
Number Of Financing Receivables Total Past Due | loan |  | 3 |  | 0 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan |  | 0 |  | 0 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan |  | 0 |  | 0 |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 1,153,945 |  | $ 1,165,457 |  |
Construction Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 2,592 |  | 0 |  |
Construction Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 |  | 0 |  |
Construction Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 |  | 0 |  |
Construction Loans [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,151,353 |  | 1,165,457 |  |
Construction Loans [Member] | Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 2,592 |  | $ 0 |  |
Small Business [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan |  | 7 |  | 11 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing |  | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross |  | $ 200,405 | [1] | $ 193,189 | 174,211 | [1]
Number Of Financing Receivables Total Past Due | loan |  | 11 |  | 21 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan |  | 2 |  | 6 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan |  | 2 |  | 4 |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 200,405 |  | $ 193,189 |  |
Small Business [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 85 |  | 136 |  |
Small Business [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 6 |  | 53 |  |
Small Business [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 8 |  | 24 |  |
Small Business [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 200,306 |  | 192,976 |  |
Small Business [Member] | Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 99 |  | $ 213 |  |
Residential Real Estate [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan |  | 9 |  | 12 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing |  | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross |  | $ 1,706,045 | [1] | $ 1,604,686 | $ 1,241,789 | [1]
Number Of Financing Receivables Total Past Due | loan |  | 88 |  | 93 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan |  | 6 |  | 5 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan |  | 73 |  | 76 |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 1,706,045 |  | $ 1,604,686 |  |
Residential Real Estate [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 2,890 |  | 2,709 |  |
Residential Real Estate [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,546 |  | 714 |  |
Residential Real Estate [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 3,341 |  | 3,922 |  |
Residential Real Estate [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,698,268 |  | 1,597,341 |  |
Residential Real Estate [Member] | Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 7,777 |  | $ 7,345 |  |
Home Equity Line of Credit [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan |  | 11 |  | 15 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing |  | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross |  | $ 1,025,815 |  | $ 1,039,611 |  |
Number Of Financing Receivables Total Past Due | loan |  | 39 |  | 42 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan |  | 5 |  | 6 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan |  | 23 |  | 21 |  |
Home Equity Line of Credit [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 834 |  | $ 1,375 |  |
Home Equity Line of Credit [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 81 |  | 381 |  |
Home Equity Line of Credit [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 2,026 |  | 1,671 |  |
Home Equity Line of Credit [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,022,874 |  | 1,036,184 |  |
Home Equity Line of Credit [Member] | Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 2,941 |  | $ 3,427 |  |
Consumer - Other [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan | [2] | 384 |  | 458 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | [2] | $ 0 |  | $ 0 |  |
Loans and Leases Receivable, Gross | [2] | $ 30,009 |  | $ 28,720 |  |
Number Of Financing Receivables Total Past Due | loan | [2] | 410 |  | 515 |  |
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan | [2] | 18 |  | 41 |  |
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan | [2] | 8 |  | 16 |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 30,009 |  | $ 28,720 |  |
Consumer - Other [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss | [2] | 541 |  | 719 |  |
Consumer - Other [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss | [2] | 157 |  | 277 |  |
Consumer - Other [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss | [2] | 18 |  | 112 |  |
Consumer - Other [Member] | Financial Asset, Not Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss | [2] | 29,293 |  | 27,612 |  |
Consumer - Other [Member] | Financial Asset, Past Due |  |  |  |  |  |
Financing Receivable, Past Due [Line Items] |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss | [2] | $ 716 |  | $ 1,108 |  |
[1] | Loan origination dates in the tables above reflect the original origination date, or the date of a material modification of a previously originated loan.
[2] | Other consumer portfolio is inclusive of deposit account overdrafts recorded as loan balances.

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