Borrowed Funds - Breakdown of Borrowed Funds (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Debt Instrument
Federal Home Loan Bank and Federal Reserve Bank advances	$ 27,750	$ 20,250
Total wholesale borrowings	27,871	20,250
Junior subordinated debentures	580	579
Subordinated notes	441	438
Total borrowed funds	28,892	21,267
Total wholesale borrowings
Debt Instrument
Total wholesale borrowings	27,871	20,250
FHLB advances
Debt Instrument
Federal Home Loan Bank and Federal Reserve Bank advances	22,750	19,250
Federal Reserve Bank term funding
Debt Instrument
Fed funds purchased	1,000	1,000
Federal Reserve Bank Discount Window
Debt Instrument
Fed funds purchased	4,000	0
Repurchase agreements
Debt Instrument
Fed funds purchased	121	0
Junior subordinated debentures
Debt Instrument
Junior subordinated debentures	580	579
Subordinated notes
Debt Instrument
Subordinated notes	$ 441	$ 438

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