Premises and Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Premises and Equipment [Abstract]
Capitalized Computer Software, Amortization	$ 26	$ 25	$ 33
Capitalized Computer Software, Unamoritize	$ 106	$ 83

Amount of expense for amortization of capitalized computer software costs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 985
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481283/985-20-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-SubTopic 20
-Topic 985
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481283/985-20-50-1

Name:	us-gaap_CapitalizedComputerSoftwareAmortization1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration