Occupancy Expense and Information Systems and Communications Expense - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Expenses [Line Items]
Depreciation and amortization		$ 842	$ 859	$ 858
Sale and leaseback transaction, gain (loss), net	$ 11
Sale leaseback transaction lease term		3 years
Finance lease right-of-use asset	167	$ 167	135
Total	$ 176	$ 176	$ 164
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term debt	Long-term debt	Long-term debt
Finance lease, right-of-use asset, accumulated amortization	$ 40	$ 40
Interest on lease liabilities		6	$ 6
Right-of-use assets	$ 500	$ 500	$ 542
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other assets	Other assets	Other assets
Lease liabilities	$ 630	$ 630
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Operating leases not yet commenced	$ 455	$ 455
Operating leases not yet commenced, lease terms	15 years	15 years
Sale Leaseback of Two Properties in United States in 2022
Expenses [Line Items]
Proceeds from sale of productive assets	$ 27