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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 | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | $ 146,774 | $ 54,057
End of Period Nonaccrual | 132,413 | 146,774
Nonaccrual With No Related Allowance | 64,628 | 71,410
Past Due 90+ Days Still Accruing | 0 | 503
Past due | 135,324 | 156,130
Interest income recognized on nonaccrual | 352 | 826
90 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Past due | 0 | 503
Commercial | Commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 101,070 | 25,356
End of Period Nonaccrual | 95,074 | 101,070
Nonaccrual With No Related Allowance | 52,460 | 60,401
Past Due 90+ Days Still Accruing | 0 | 0
Past due | 95,074 | 101,070
Interest income recognized on nonaccrual | 61 | 22
Commercial | Commercial real estate | 90 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Past due | 0 | 0
Commercial | Commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 16,985 | 10,911
End of Period Nonaccrual | 12,416 | 16,985
Nonaccrual With No Related Allowance | 11,425 | 6,436
Past Due 90+ Days Still Accruing | 0 | 0
Past due | 12,416 | 16,985
Interest income recognized on nonaccrual | 43 | 101
Commercial | Commercial and industrial | 90 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Past due | 0 | 0
Commercial | Commercial construction |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 384 | 737
End of Period Nonaccrual | 384 | 384
Nonaccrual With No Related Allowance | 0 | 285
Past Due 90+ Days Still Accruing | 0 | 0
Past due | 384 | 3,983
Interest income recognized on nonaccrual | 0 | 0
Commercial | Commercial construction | 90 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Past due | 0 | 0
Commercial | Business banking |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 17,122 | 9,863
End of Period Nonaccrual | 14,426 | 17,122
Nonaccrual With No Related Allowance | 397 | 3,890
Past Due 90+ Days Still Accruing | 0 | 371
Past due | 15,647 | 19,486
Interest income recognized on nonaccrual | 137 | 275
Commercial | Business banking | 90 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Past due | 0 | 371
Consumer | Consumer real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 11,117 | 6,063
End of Period Nonaccrual | 7,949 | 11,117
Nonaccrual With No Related Allowance | 345 | 398
Past Due 90+ Days Still Accruing | 0 | 132
Past due | 9,498 | 14,304
Interest income recognized on nonaccrual | 110 | 423
Consumer | Consumer real estate | 90 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Past due | 0 | 132
Consumer | Other consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 96 | 1,127
End of Period Nonaccrual | 2,163 | 96
Nonaccrual With No Related Allowance | 0 | 0
Past Due 90+ Days Still Accruing | 0 | 0
Past due | 2,304 | 302
Interest income recognized on nonaccrual | 1 | 4
Consumer | Other consumer | 90 Days Past Due |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Past due | $ 0 | $ 0

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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=121599337&loc=SL82919258-210447 + Details
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- Definition Amount of financing receivable on nonaccrual status with no allowance for credit loss. + 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 (d) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447 + Details
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