Loans and Leases - Schedule of Loans Pledged as Collateral (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
FHLB of Atlanta
Pledged non-PCD loans (contractual balance)	$ 133,202	$ 70,781	$ 69,790
FHLB of Atlanta \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Lendable collateral value of pledged non-PCD loans	14,975	14,918
Less: Advances	0	4,250
Less: Letters of Credit	1,450	1,450
Available borrowing capacity	13,525	9,218
Pledged non-PCD loans (contractual balance)	24,498	23,491
FRB \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Pledged non-PCD loans (contractual balance)	6,164	5,697
FRB
Lendable collateral value of pledged non-PCD loans	4,989	4,203
Less: Advances	0	0
Available borrowing capacity	$ 4,989	$ 4,203

Advances from Federal Reserve Bank

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Federal Reserve Bank

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Federal Reserve Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds

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Federal Reserve Bank, Advances, General Debt Obligations, Maximum Amount Available

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Letters Of Credit From Federal Home Loan Bank

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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