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Loans and Leases - Narrative (Details) - USD ($) $ in Millions | Jan. 03, 2022 | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Receivables [Abstract] |  |  |
Financing receivable, accrued interest receivable |  | $ 142.0 | $ 87.0
Financing receivable, threshold period past due |  | 30 days |
Other real estate owned |  | $ 45.0 | 40.0
Financing receivable, troubled debt restructuring, commitment to lend |  | $ 1.0 | $ 0.4
CIT Group Inc. |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans and leases | $ 32,714.0 |  |
CIT Group Inc. | Non-PCD |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Purchase accounting adjustment of discount | (61.0) |  |
CIT Group Inc. | Non-PCD | Commercial | Leases |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans and leases | $ 29,500.0 |  |

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- Definition Amount, after allowance for credit loss, of accrued interest on financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3A -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267960-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL120267845-210446 + Details
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