Fair Value - Schedule of Carrying Values and Estimated Fair Values for Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Financial Assets
Investment in marketable equity securities	$ 94	$ 98
Investment securities held to maturity	9,832	3,809
Fair value of derivative financial instruments	80	3
Financial Liabilities
Fair value of derivative financial instruments	308	1
Reported Value Measurement
Financial Assets
Cash and due from banks	583	338
Interest-earning deposits at banks	6,476	9,115
Investment in marketable equity securities	94	98
Investment securities available for sale	9,210	9,203
Investment securities held to maturity	9,832	3,809
Loans held for sale	35	99
Net loans	64,739	32,193
Accrued interest receivable	258	134
Federal Home Loan Bank stock	83	40
Mortgage and other servicing rights	28	23
Fair value of derivative financial instruments	80
Financial Liabilities
Deposits	89,329
Credit balances of factoring clients	1,070
Securities sold under customer repurchase agreements	646	589
Long-term borrowings	3,810	1,195
Reserve for off-balance sheet credit exposure	27	8
Fair value of derivative financial instruments	308
Deposits with no stated maturity		48,925
Time deposits		2,481
Estimate of Fair Value Measurement
Financial Assets
Cash and due from banks	583	338
Interest-earning deposits at banks	6,476	9,115
Investment in marketable equity securities	94	98
Investment securities available for sale	9,210	9,203
Investment securities held to maturity	8,812	3,759
Loans held for sale	37	99
Net loans	62,143	31,890
Accrued interest receivable	258	134
Federal Home Loan Bank stock	83	40
Mortgage and other servicing rights	38	23
Fair value of derivative financial instruments	80
Financial Liabilities
Deposits	89,240
Credit balances of factoring clients	1,070
Securities sold under customer repurchase agreements	646	589
Long-term borrowings	3,699	1,222
Reserve for off-balance sheet credit exposure	27	8
Fair value of derivative financial instruments	308
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	583	338
Interest-earning deposits at banks	6,476	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	0
Credit balances of factoring clients	0
Securities sold under customer repurchase agreements	0	0
Long-term borrowings	0	0
Reserve for off-balance sheet credit exposure	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 in marketable equity securities	62	64
Investment securities available for sale	9,030	8,996
Investment securities held to maturity	8,812	3,759
Loans held for sale	22	99
Net loans	1,593	0
Accrued interest receivable	258	134
Federal Home Loan Bank stock	83	40
Mortgage and other servicing rights	0	0
Fair value of derivative financial instruments	79
Financial Liabilities
Deposits	89,240
Credit balances of factoring clients	0
Securities sold under customer repurchase agreements	646	589
Long-term borrowings	3,683	1,222
Reserve for off-balance sheet credit exposure	27	8
Fair value of derivative financial instruments	308
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 in marketable equity securities	0	0
Investment securities available for sale	180	207
Investment securities held to maturity	0	0
Loans held for sale	15	0
Net loans	60,550	31,890
Accrued interest receivable	0	0
Federal Home Loan Bank stock	0	0
Mortgage and other servicing rights	38	23
Fair value of derivative financial instruments	1
Financial Liabilities
Deposits	0
Credit balances of factoring clients	1,070
Securities sold under customer repurchase agreements	0	0
Long-term borrowings	16	0
Reserve for off-balance sheet credit exposure	0	0
Fair value of derivative financial instruments	$ 0
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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