Commitments, Contingent Liabilities and Guarantees - Risk Rating Under the Risk Rating System (Details) - Commitments to extend credit - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Line of Credit Facility
Commitments	$ 84,505	$ 83,437
Pass
Line of Credit Facility
Commitments	82,292	81,345
Special mention
Line of Credit Facility
Commitments	1,017	976
Substandard
Line of Credit Facility
Commitments	$ 1,196	$ 1,116

Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Name:	us-gaap_CommitmentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant