Leases, Premises and Equipment - Premises and Equipment (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Leases [Abstract]
Premises and equipment	$ 1,014	$ 1,131
Less: Accumulated depreciation	(528)	(569)
Premises and equipment, net	$ 486	$ 562

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant