Mortgage Banking Activity - MSR Carrying Amount and Accumulated Amortization (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Mortgage Banking [Abstract]
Gross Carrying Amount	$ 25	$ 25
Accumulated Amortization	(7)	(7)
Net Carrying Amount	$ 18	$ 18

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-1

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-2

Name:	us-gaap_ServicingAssetAtAmortizedValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant