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Allowance for Credit Losses - Allowance for Credit Loss Activity (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | $ 62,224 | $ 60,996
Provision for credit losses on loans |  | 131,421 | 14,873
Charge-offs |  | (106,365) | (16,189)
Recoveries |  | 2,986 | 2,544
Net (Charge-offs)/Recoveries |  | (103,379) | (13,645)
Balance at End of Period |  | 117,612 | 62,224
Customer fraud, check kiting |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Charge-offs | $ (58,700) |  |
Commercial | Commercial real estate |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 30,577 | 33,707
Provision for credit losses on loans |  | 56,489 | 397
Charge-offs |  | (26,460) | (3,664)
Recoveries |  | 240 | 137
Net (Charge-offs)/Recoveries |  | (26,220) | (3,527)
Balance at End of Period |  | 65,656 | 30,577
Commercial | Commercial and industrial |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 15,681 | 11,596
Provision for credit losses on loans |  | 65,288 | 11,625
Charge-offs |  | (74,282) | (8,928)
Recoveries |  | 1,560 | 1,388
Net (Charge-offs)/Recoveries |  | (72,722) | (7,540)
Balance at End of Period |  | 16,100 | 15,681
Commercial | Other Consumer |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 7,900 | 7,983
Provision for credit losses on loans |  | 2,986 | 318
Charge-offs |  | (454) | (406)
Recoveries |  | 183 | 5
Net (Charge-offs)/Recoveries |  | (271) | (401)
Balance at End of Period |  | 7,239 | 7,900
Commercial | Business banking |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 0 |
Provision for credit losses on loans |  | 5,303 |
Charge-offs |  | (2,612) |
Recoveries |  | 328 |
Net (Charge-offs)/Recoveries |  | (2,284) |
Balance at End of Period |  | 15,917 | 0
Consumer | Consumer real estate |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 6,337 | 6,187
Provision for credit losses on loans |  | (368) | 866
Charge-offs |  | (667) | (1,353)
Recoveries |  | 187 | 637
Net (Charge-offs)/Recoveries |  | (480) | (716)
Balance at End of Period |  | 10,014 | 6,337
Consumer | Other consumer |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 1,729 | 1,523
Provision for credit losses on loans |  | 1,723 | 1,667
Charge-offs |  | (1,890) | (1,838)
Recoveries |  | 488 | 377
Net (Charge-offs)/Recoveries |  | (1,402) | (1,461)
Balance at End of Period |  | 2,686 | 1,729
Impact of ASU 2016-13 Adoption |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 27,346 |
Balance at End of Period |  |  | 27,346
Impact of ASU 2016-13 Adoption | Commercial | Commercial real estate |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 4,810 |
Balance at End of Period |  |  | 4,810
Impact of ASU 2016-13 Adoption | Commercial | Commercial and industrial |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 7,853 |
Balance at End of Period |  |  | 7,853
Impact of ASU 2016-13 Adoption | Commercial | Other Consumer |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | (3,376) |
Balance at End of Period |  |  | (3,376)
Impact of ASU 2016-13 Adoption | Commercial | Business banking |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 12,898 |
Balance at End of Period |  |  | 12,898
Impact of ASU 2016-13 Adoption | Consumer | Consumer real estate |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | 4,525 |
Balance at End of Period |  |  | 4,525
Impact of ASU 2016-13 Adoption | Consumer | Other consumer |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |
Balance at beginning of period |  | $ 636 |
Balance at End of Period |  |  | $ 636

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