Deposits and Borrowings - Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total long-term debt	$ 58,498	$ 42,266
Total short-term borrowings and long-term debt	58,938	43,086
EUR denominated unsecured notes	30,489	27,219
Euro
Debt Instrument [Line Items]
EUR denominated unsecured notes	$ 1,200	1,400
Securitized debt obligations
Debt Instrument [Line Items]
Weighted average interest rate	2.02%
Carrying value	$ 17,466	14,994
Total senior and subordinated notes
Debt Instrument [Line Items]
Carrying value	$ 30,489	27,219
Senior notes \| Total unsecured senior debt
Debt Instrument [Line Items]
Weighted average interest rate	3.16%
Carrying value	$ 25,279	21,684
Senior notes \| Fixed unsecured senior debt
Debt Instrument [Line Items]
Weighted average interest rate	3.23%
Carrying value	$ 23,444	19,975
Senior notes \| Floating unsecured senior debt
Debt Instrument [Line Items]
Weighted average interest rate	2.28%
Carrying value	$ 1,835	1,709
Subordinated notes \| Fixed unsecured subordinated debt
Debt Instrument [Line Items]
Weighted average interest rate	3.52%
Carrying value	$ 5,210	5,535
FHLB advances
Debt Instrument [Line Items]
Weighted average interest rate	1.70%
Carrying value	$ 10,500	0
Finance lease liabilities
Debt Instrument [Line Items]
Weighted average interest rate	3.65%
Carrying value	$ 43	53
Total other long-term borrowings
Debt Instrument [Line Items]
Carrying value	$ 10,543	$ 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	1.96%
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	1.62%
Minimum \| Finance lease liabilities
Debt Instrument [Line Items]
Stated interest rates	0.30%
Maximum \| Securitized debt obligations
Debt Instrument [Line Items]
Stated interest rates	3.49%
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	2.86%
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	1.77%
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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