Leases - Summary of Additional Balance Sheet Information (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Accrued income and other assets	Accrued income and other assets
Operating lease assets	$ 595	$ 630
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Accrued expense and other liabilities	Accrued expense and other liabilities
Operating lease liabilities	$ 676	$ 711
Finance leases:
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Premises and equipment	Premises and equipment
Finance lease, right of use asset, before accumulated depreciation	$ 18	$ 28
Accumulated depreciation	(13)	(19)
Property and equipment, net	$ 5	$ 9
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term debt	Long-term debt
Finance lease liabilities	$ 7	$ 11