Business Combinations - Schedule of Business Acquisition, Pro Forma Information (Details) - CIT Group Inc. - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Business acquisition, pro forma net income (loss)	$ 1,225	$ 1,497
Interest income
Business Acquisition [Line Items]
Business acquisition, pro forma revenue	3,413	2,867
Noninterest income
Business Acquisition [Line Items]
Business acquisition, pro forma revenue	$ 1,705	$ 2,537

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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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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
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