Bank Premises and Equipment - Summary of Bank Premises and Equipment (Details) - USD ($) $ in Millions		Jun. 30, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization		$ (3,363)	$ (3,360)
Total bank premises and equipment	[1]	2,275	2,187
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross		2,506	2,492
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross		1,729	1,699
Land and and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross		633	640
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross		608	568
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross		140	124
Land and improvements held for sale
Property, Plant and Equipment [Line Items]
Property and equipment, gross		16	17
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross		6	7
Other property
Property, Plant and Equipment [Line Items]
Land improvements		$ 23	$ 27

[1] Includes $22 and $24 of bank premises and equipment held for sale at June 30, 2023 and December 31, 2022, respectively.