PREMISES, EQUIPMENT, AND SOFTWARE - Schedule of Premises and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Total premises and equipment, gross	$ 1,685	$ 1,708
Accumulated depreciation and amortization	(810)	(813)
Total premises and equipment, net	875	895
Land and land improvements
Property, Plant and Equipment [Line Items]
Total premises and equipment, gross	$ 144	143
Land and land improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful life	10 years
Land and land improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful life	75 years
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Total premises and equipment, gross	$ 887	875
Buildings and leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful life	5 years
Buildings and leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful life	60 years
Furniture, fixtures and equipment
Property, Plant and Equipment [Line Items]
Total premises and equipment, gross	$ 601	613
Furniture, fixtures and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life	4 years
Furniture, fixtures and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life	20 years
Construction in progress
Property, Plant and Equipment [Line Items]
Total premises and equipment, gross	$ 53	$ 77