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Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) $ in Thousands | 6 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 USD ($) loan | Dec. 31, 2020 USD ($) loan | Dec. 31, 2019 USD ($)
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 7,007,351 | $ 7,225,860 |
Non - performing | 112,619 | 146,774 | $ 54,057
Financial Asset, Not Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 6,878,389 | 7,069,730 |
Financial Asset, Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 128,962 | 156,130 |
30 to 59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 15,063 | 2,888 |
60 to 89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,281 | 5,965 |
90 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | 503 |
Commercial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 5,499,044 | $ 5,673,707 |
Commercial | CARES Act, Paycheck Protection Program Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Number of modified loans | loan | 42 | 52 |
Modified loans | $ 68,700 | $ 195,600 |
Commercial | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,740,296 | 2,791,947 |
Non - performing | 80,067 | 101,070 | 25,356
Commercial | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,546,247 | 1,559,552 |
Non - performing | 12,198 | 16,985 | 10,911
Commercial | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 467,871 | 466,077 |
Non - performing | 385 | 384 | 737
Commercial | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,070,875 | 1,160,067 |
Non - performing | 11,064 | 17,122 | 9,863
Commercial | Financial Asset, Not Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,648,221 | 2,690,877 |
Commercial | Financial Asset, Not Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,534,049 | 1,542,567 |
Commercial | Financial Asset, Not Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 466,987 | 462,094 |
Commercial | Financial Asset, Not Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,057,279 | 1,140,581 |
Commercial | Financial Asset, Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 92,075 | 101,070 |
Commercial | Financial Asset, Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 12,198 | 16,985 |
Commercial | Financial Asset, Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 885 | 3,983 |
Commercial | Financial Asset, Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 13,597 | 19,486 |
Commercial | 30 to 59 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial | 30 to 59 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 12,007 | 0 |
Commercial | 30 to 59 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 19 |
Commercial | 30 to 59 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,311 | 1,614 |
Commercial | 60 to 89 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 500 | 0 |
Commercial | 60 to 89 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial | 60 to 89 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 3,580 |
Commercial | 60 to 89 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 222 | 379 |
Commercial | 90 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | 0 |
Commercial | 90 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | 0 |
Commercial | 90 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | 0 |
Commercial | 90 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | 371 |
Consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,508,307 | 1,552,153 |
Consumer | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | 303,900 |
Consumer | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,093,878 | 1,167,332 |
Non - performing | 8,783 | 11,117 | 6,063
Consumer | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 88,184 | 80,885 |
Non - performing | 121 | 96 | $ 1,127
Consumer | Financial Asset, Not Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,083,947 | 1,153,028 |
Consumer | Financial Asset, Not Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 87,905 | 80,583 |
Consumer | Financial Asset, Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 9,930 | 14,304 |
Consumer | Financial Asset, Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 278 | 302 |
Consumer | 30 to 59 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 640 | 1,087 |
Consumer | 30 to 59 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 105 | 168 |
Consumer | 60 to 89 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 507 | 1,968 |
Consumer | 60 to 89 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 52 | 37 |
Consumer | 90 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | 132 |
Consumer | 90 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total |  | $ 0 |

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