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Allowance for Credit Losses - Loans on Nonaccrual Status and Loans Past Due 90 Days or More and Still Accruing (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2021 | Dec. 31, 2020
Financing Receivable, Nonaccrual [Line Items] |  |  |
Beginning of Period Nonaccrual |  | $ 146,774 | $ 54,057
End of Period Nonaccrual | $ 112,619 | 112,619 | 146,774
Nonaccrual With No Related Allowance | 60,340 | 60,340 | 71,410
Past Due 90+ Days Still Accruing |  |  | 503
Interest income recognized on nonaccrual | 426 | 776 | 826
Commercial | Commercial real estate |  |  |
Financing Receivable, Nonaccrual [Line Items] |  |  |
Beginning of Period Nonaccrual |  | 101,070 | 25,356
End of Period Nonaccrual | 80,067 | 80,067 | 101,070
Nonaccrual With No Related Allowance | 47,648 | 47,648 | 60,401
Past Due 90+ Days Still Accruing |  |  | 0
Interest income recognized on nonaccrual | 5 | 66 | 22
Commercial | Commercial and industrial |  |  |
Financing Receivable, Nonaccrual [Line Items] |  |  |
Beginning of Period Nonaccrual |  | 16,985 | 10,911
End of Period Nonaccrual | 12,198 | 12,198 | 16,985
Nonaccrual With No Related Allowance | 11,183 | 11,183 | 6,436
Past Due 90+ Days Still Accruing |  |  | 0
Interest income recognized on nonaccrual | 72 | 115 | 101
Commercial | Commercial construction |  |  |
Financing Receivable, Nonaccrual [Line Items] |  |  |
Beginning of Period Nonaccrual |  | 384 | 737
End of Period Nonaccrual | 385 | 385 | 384
Nonaccrual With No Related Allowance | 0 | 0 | 285
Past Due 90+ Days Still Accruing |  |  | 0
Interest income recognized on nonaccrual | 0 | 0 | 0
Commercial | Business banking |  |  |
Financing Receivable, Nonaccrual [Line Items] |  |  |
Beginning of Period Nonaccrual |  | 17,122 | 9,863
End of Period Nonaccrual | 11,064 | 11,064 | 17,122
Nonaccrual With No Related Allowance | 1,508 | 1,508 | 3,890
Past Due 90+ Days Still Accruing |  |  | 371
Interest income recognized on nonaccrual | 139 | 275 | 275
Consumer | Consumer real estate |  |  |
Financing Receivable, Nonaccrual [Line Items] |  |  |
Beginning of Period Nonaccrual |  | 11,117 | 6,063
End of Period Nonaccrual | 8,783 | 8,783 | 11,117
Nonaccrual With No Related Allowance | 0 | 0 | 398
Past Due 90+ Days Still Accruing |  |  | 132
Interest income recognized on nonaccrual | 210 | 319 | 423
Consumer | Other consumer |  |  |
Financing Receivable, Nonaccrual [Line Items] |  |  |
Beginning of Period Nonaccrual |  | 96 | 1,127
End of Period Nonaccrual | 121 | 121 | 96
Nonaccrual With No Related Allowance | 0 | 0 | 0
Past Due 90+ Days Still Accruing |  |  | 0
Interest income recognized on nonaccrual | $ 0 | $ 1 | $ 4

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- Definition Amount of interest income on financing receivable on nonaccrual status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 + Details
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