Business Combinations - Schedule of Business Acquisition, Pro Forma Information (Details) - CIT Group Inc. - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Business Acquisition [Line Items]
Business acquisition, pro forma net income (loss)	$ 338	$ 340	$ 955	$ 1,112
Interest income
Business Acquisition [Line Items]
Business acquisition, pro forma revenue	906	714	2,373	2,152
Noninterest income
Business Acquisition [Line Items]
Business acquisition, pro forma revenue	$ 433	$ 515	$ 1,276	$ 2,014

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
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-Publisher FASB
-Name Accounting Standards Codification
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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