Deposits and Borrowings - Long-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total long-term debt	$ 54,079	$ 42,266
Total short-term borrowings and long-term debt	54,607	43,086
EUR denominated unsecured notes	30,615	27,219
Euro
Debt Instrument [Line Items]
EUR denominated unsecured notes	$ 1,100	1,400
Securitized debt obligations
Debt Instrument [Line Items]
Weighted average interest rate	2.27%
Carrying value	$ 15,926	14,994
Total senior and subordinated notes
Debt Instrument [Line Items]
Carrying value	$ 30,615	27,219
Senior notes \| Total unsecured senior debt
Debt Instrument [Line Items]
Weighted average interest rate	3.46%
Carrying value	$ 25,554	21,684
Senior notes \| Fixed unsecured senior debt
Debt Instrument [Line Items]
Weighted average interest rate	3.44%
Carrying value	$ 23,957	19,975
Senior notes \| Floating unsecured senior debt
Debt Instrument [Line Items]
Weighted average interest rate	3.77%
Carrying value	$ 1,597	1,709
Subordinated notes \| Fixed unsecured subordinated debt
Debt Instrument [Line Items]
Weighted average interest rate	3.52%
Carrying value	$ 5,061	5,535
FHLB advances
Debt Instrument [Line Items]
Weighted average interest rate	3.13%
Carrying value	$ 7,500	0
Finance lease liabilities
Debt Instrument [Line Items]
Weighted average interest rate	3.92%
Carrying value	$ 38	53
Total other long-term borrowings
Debt Instrument [Line Items]
Carrying value	$ 7,538	$ 53
Minimum \| Securitized debt obligations
Debt Instrument [Line Items]
Stated interest rates	0.32%
Minimum \| Senior notes \| Fixed unsecured senior debt
Debt Instrument [Line Items]
Stated interest rates	0.80%
Minimum \| Senior notes \| Floating unsecured senior debt
Debt Instrument [Line Items]
Stated interest rates	3.53%
Minimum \| Subordinated notes \| Fixed unsecured subordinated debt
Debt Instrument [Line Items]
Stated interest rates	2.36%
Minimum \| FHLB advances
Debt Instrument [Line Items]
Stated interest rates	3.07%
Minimum \| Finance lease liabilities
Debt Instrument [Line Items]
Stated interest rates	0.30%
Maximum \| Securitized debt obligations
Debt Instrument [Line Items]
Stated interest rates	3.74%
Maximum \| Senior notes \| Fixed unsecured senior debt
Debt Instrument [Line Items]
Stated interest rates	5.27%
Maximum \| Senior notes \| Floating unsecured senior debt
Debt Instrument [Line Items]
Stated interest rates	4.31%
Maximum \| Subordinated notes \| Fixed unsecured subordinated debt
Debt Instrument [Line Items]
Stated interest rates	4.20%
Maximum \| FHLB advances
Debt Instrument [Line Items]
Stated interest rates	3.19%
Maximum \| Finance lease liabilities
Debt Instrument [Line Items]
Stated interest rates	9.91%

Amount of short-term and long-term debt and lease obligation.

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