Fair Value - Schedule of Carrying Values and Estimated Fair Values for Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Financial Assets
Investment in marketable equity securities	$ 85	$ 95
Investment securities available for sale	9,061	8,995
Investment securities held to maturity	10,381	10,279
Interest rate & other derivative — non-qualifying hedges	547	159
Financial Liabilities
Fair value of derivative financial instruments	791	486
Reported Value Measurement
Financial Assets
Cash and due from banks	1,598	518
Interest earning deposits at banks	38,522	5,025
Investment in marketable equity securities	85	95
Investment securities available for sale	9,061	8,995
Investment securities held to maturity	10,381	10,279
Loans held for sale	90	52
Net loans	134,556	67,720
Accrued interest receivable	772	329
Federal Home Loan Bank stock	393	197
Mortgage and other servicing rights	25	25
Interest rate & other derivative — non-qualifying hedges	547	159
Financial Liabilities
Deposits with no stated maturity	126,922
Deposits with no stated maturity		78,798
Time deposits	13,128	10,610
Credit balances of factoring clients	1,126	995
Securities sold under customer repurchase agreements	509	436
Other short-term debt	500	1,750
Long-term borrowings	45,078	4,452
Accrued interest payable	150	57
Fair value of derivative financial instruments	791	486
Estimate of Fair Value Measurement
Financial Assets
Cash and due from banks	1,598	518
Interest earning deposits at banks	38,522	5,025
Investment in marketable equity securities	85	95
Investment securities available for sale	9,061	8,995
Investment securities held to maturity	8,993	8,795
Loans held for sale	90	49
Net loans	132,148	64,312
Accrued interest receivable	772	329
Federal Home Loan Bank stock	393	197
Mortgage and other servicing rights	45	47
Interest rate & other derivative — non-qualifying hedges	547	159
Financial Liabilities
Deposits with no stated maturity	126,922
Deposits with no stated maturity		78,798
Time deposits	13,055	10,504
Credit balances of factoring clients	1,126	995
Securities sold under customer repurchase agreements	509	436
Other short-term debt	500	1,750
Long-term borrowings	45,048	4,330
Accrued interest payable	150	57
Fair value of derivative financial instruments	791	486
Estimate of Fair Value Measurement \| Level 1
Financial Assets
Cash and due from banks	1,598	518
Interest earning deposits at banks	38,522	5,025
Investment in marketable equity securities	29	32
Investment securities available for sale	0	0
Investment securities held to maturity	0	0
Loans held for sale	0	0
Net loans	0	0
Accrued interest receivable	0	0
Federal Home Loan Bank stock	0	0
Mortgage and other servicing rights	0	0
Interest rate & other derivative — non-qualifying hedges	0	0
Financial Liabilities
Deposits with no stated maturity	0
Deposits with no stated maturity		0
Time deposits	0	0
Credit balances of factoring clients	0	0
Securities sold under customer repurchase agreements	0	0
Other short-term debt	0	0
Long-term borrowings	0	0
Accrued interest payable	0	0
Fair value of derivative financial instruments	0	0
Estimate of Fair Value Measurement \| Level 2
Financial Assets
Cash and due from banks	0	0
Interest earning deposits at banks	0	0
Investment in marketable equity securities	56	63
Investment securities available for sale	8,901	8,821
Investment securities held to maturity	8,993	8,795
Loans held for sale	9	4
Net loans	1,576	1,679
Accrued interest receivable	772	329
Federal Home Loan Bank stock	393	197
Mortgage and other servicing rights	0	0
Interest rate & other derivative — non-qualifying hedges	546	159
Financial Liabilities
Deposits with no stated maturity	126,922
Deposits with no stated maturity		78,798
Time deposits	13,055	10,504
Credit balances of factoring clients	0	0
Securities sold under customer repurchase agreements	509	436
Other short-term debt	500	1,750
Long-term borrowings	45,048	4,312
Accrued interest payable	150	57
Fair value of derivative financial instruments	790	486
Estimate of Fair Value Measurement \| Level 3
Financial Assets
Cash and due from banks	0	0
Interest earning deposits at banks	0	0
Investment in marketable equity securities	0	0
Investment securities available for sale	160	174
Investment securities held to maturity	0	0
Loans held for sale	81	45
Net loans	130,572	62,633
Accrued interest receivable	0	0
Federal Home Loan Bank stock	0	0
Mortgage and other servicing rights	45	47
Interest rate & other derivative — non-qualifying hedges	1	0
Financial Liabilities
Deposits with no stated maturity	0
Deposits with no stated maturity		0
Time deposits	0	0
Credit balances of factoring clients	1,126	995
Securities sold under customer repurchase agreements	0	0
Other short-term debt	0	0
Long-term borrowings	0	18
Accrued interest payable	0	0
Fair value of derivative financial instruments	$ 1	$ 0

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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