Loans and Leases - Schedule of Financing Receivable Purchased With Credit Deterioration (Details) - CIT Group Inc. $ in Millions	Jan. 03, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
UPB	$ 3,562
Initial PCD ACL	(284)
Fair value discount, net of the PCD Gross-Up	(45)
Purchase price	$ 3,233

Financing Receivable, Purchased with Credit Deterioration, Gross-Up Amount

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount at par value of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447

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- Definition

Amount at purchase price of financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447

+ Details

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- Definition

Amount of discount (premium) attributable to other factors on financing receivable purchased with credit deterioration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 19
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919265-210447

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