Fair Value - Schedule of Carrying Values and Estimated Fair Values for Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Financial Assets
Investment securities held to maturity	$ 10,074	$ 3,809
Investment in marketable equity securities	100	98
Fair value of derivative financial instruments	110	0
Financial Liabilities
Fair value of derivative financial instruments	204	0
Reported Value Measurement
Financial Assets
Cash and due from banks	523	338
Interest-earning deposits at banks	9,285	9,115
Investment securities available for sale	9,295	9,203
Investment securities held to maturity	10,074	3,809
Investment in marketable equity securities	100	98
Loans held for sale	81	99
Net loans	62,489	32,193
Income earned not collected	247	134
Federal Home Loan Bank stock	39	40
Mortgage and other servicing rights	28	23
Fair value of derivative financial instruments	110
Financial Liabilities
Deposits	91,597
Securities sold under customer repurchase agreements	616	589
Long-term borrowings	2,672	1,195
Credit balances of factoring clients	1,150
Accrued interest payable	24	8
Fair value of derivative financial instruments	204
Deposits with no stated maturity		48,925
Time deposits		2,481
Estimate of Fair Value Measurement
Financial Assets
Cash and due from banks	523	338
Interest-earning deposits at banks	9,285	9,115
Investment securities available for sale	9,295	9,203
Investment securities held to maturity	9,457	3,759
Investment in marketable equity securities	100	98
Loans held for sale	81	99
Net loans	61,331	31,890
Income earned not collected	247	134
Federal Home Loan Bank stock	39	40
Mortgage and other servicing rights	35	23
Fair value of derivative financial instruments	110
Financial Liabilities
Deposits	91,572
Securities sold under customer repurchase agreements	616	589
Long-term borrowings	2,621	1,222
Credit balances of factoring clients	1,150
Accrued interest payable	24	8
Fair value of derivative financial instruments	204
Deposits with no stated maturity		48,925
Time deposits		2,471
Estimate of Fair Value Measurement \| Level 1
Financial Assets
Cash and due from banks	523	338
Interest-earning deposits at banks	9,285	9,115
Investment securities available for sale	0	0
Investment securities held to maturity	0	0
Investment in marketable equity securities	33	34
Loans held for sale	0	0
Net loans	0	0
Income earned not collected	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	0
Securities sold under customer repurchase agreements	0	0
Long-term borrowings	0	0
Credit balances of factoring clients	0
Accrued interest payable	0	0
Fair value of derivative financial instruments	0
Deposits with no stated maturity		0
Time deposits		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 securities available for sale	9,109	8,996
Investment securities held to maturity	9,457	3,759
Investment in marketable equity securities	67	64
Loans held for sale	65	99
Net loans	1,574	0
Income earned not collected	247	134
Federal Home Loan Bank stock	39	40
Mortgage and other servicing rights	0	0
Fair value of derivative financial instruments	109
Financial Liabilities
Deposits	91,572
Securities sold under customer repurchase agreements	616	589
Long-term borrowings	2,606	1,222
Credit balances of factoring clients	0
Accrued interest payable	24	8
Fair value of derivative financial instruments	203
Deposits with no stated maturity		48,925
Time deposits		2,471
Estimate of Fair Value Measurement \| Level 3
Financial Assets
Cash and due from banks	0	0
Interest-earning deposits at banks	0	0
Investment securities available for sale	186	207
Investment securities held to maturity	0	0
Investment in marketable equity securities	0	0
Loans held for sale	16	0
Net loans	59,757	31,890
Income earned not collected	0	0
Federal Home Loan Bank stock	0	0
Mortgage and other servicing rights	35	23
Fair value of derivative financial instruments	1
Financial Liabilities
Deposits	0
Securities sold under customer repurchase agreements	0	0
Long-term borrowings	15	0
Credit balances of factoring clients	1,150
Accrued interest payable	0	0
Fair value of derivative financial instruments	$ 1
Deposits with no stated maturity		0
Time deposits		$ 0

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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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