Fair Value - Schedule of Carrying Values and Estimated Fair Values for Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Financial Assets
Investment in marketable equity securities	$ 95	$ 98
Investment securities available for sale	8,995	9,203
Investment securities held to maturity	10,279	3,809
Fair value of derivative financial instruments	159	3
Financial Liabilities
Fair value of derivative financial instruments	486	0
Reported Value Measurement
Financial Assets
Cash and due from banks	518	338
Interest earning deposits at banks	5,025	9,115
Investment in marketable equity securities	95	98
Investment securities available for sale	8,995	9,203
Investment securities held to maturity	10,279	3,809
Loans held for sale	52	99
Net loans	67,720	32,193
Accrued interest receivable	329	134
Federal Home Loan Bank stock	197	40
Mortgage and other servicing rights	25	23
Fair value of derivative financial instruments	159
Financial Liabilities
Deposits with no stated maturity	78,798	48,925
Time deposits	10,610	2,481
Credit balances of factoring clients	995
Securities sold under customer repurchase agreements	436	589
Other short-term debt	1,750
Long-term borrowings	4,452	1,195
Accrued interest payable	57	8
Fair value of derivative financial instruments	486
Estimate of Fair Value Measurement
Financial Assets
Cash and due from banks	518	338
Interest earning deposits at banks	5,025	9,115
Investment in marketable equity securities	95	98
Investment securities available for sale	8,995	9,203
Investment securities held to maturity	8,795	3,759
Loans held for sale	49	99
Net loans	64,312	31,890
Accrued interest receivable	329	134
Federal Home Loan Bank stock	197	40
Mortgage and other servicing rights	47	23
Fair value of derivative financial instruments	159
Financial Liabilities
Deposits with no stated maturity	78,798	48,925
Time deposits	10,504	2,471
Credit balances of factoring clients	995
Securities sold under customer repurchase agreements	436	589
Other short-term debt	1,750
Long-term borrowings	4,330	1,222
Accrued interest payable	57	8
Fair value of derivative financial instruments	486
Estimate of Fair Value Measurement \| Level 1
Financial Assets
Cash and due from banks	518	338
Interest earning deposits at banks	5,025	9,115
Investment in marketable equity securities	32	34
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
Fair value of derivative financial instruments	0
Financial Liabilities
Deposits with no stated maturity	0	0
Time deposits	0	0
Credit balances of factoring clients	0
Securities sold under customer repurchase agreements	0	0
Other short-term debt	0
Long-term borrowings	0	0
Accrued interest payable	0	0
Fair value of derivative financial instruments	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	63	64
Investment securities available for sale	8,821	8,996
Investment securities held to maturity	8,795	3,759
Loans held for sale	4	99
Net loans	1,679	0
Accrued interest receivable	329	134
Federal Home Loan Bank stock	197	40
Mortgage and other servicing rights	0	0
Fair value of derivative financial instruments	159
Financial Liabilities
Deposits with no stated maturity	78,798	48,925
Time deposits	10,504	2,471
Credit balances of factoring clients	0
Securities sold under customer repurchase agreements	436	589
Other short-term debt	1,750
Long-term borrowings	4,312	1,222
Accrued interest payable	57	8
Fair value of derivative financial instruments	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	174	207
Investment securities held to maturity	0	0
Loans held for sale	45	0
Net loans	62,633	31,890
Accrued interest receivable	0	0
Federal Home Loan Bank stock	0	0
Mortgage and other servicing rights	47	23
Fair value of derivative financial instruments	0
Financial Liabilities
Deposits with no stated maturity	0	0
Time deposits	0	0
Credit balances of factoring clients	995
Securities sold under customer repurchase agreements	0	0
Other short-term debt	0
Long-term borrowings	18	0
Accrued interest payable	0	$ 0
Fair value of derivative financial instruments	$ 0

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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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