v3.26.1
Fair Value Measurement (Narrative) (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Fair Value Disclosures [Abstract]    
Contractually Specified Servicing Fee, Late Fee, and Ancillary Fee Earned in Exchange for Servicing Financial Asset $ 6 $ 6
Fair Value, Option, Quantitative Disclosures [Line Items]    
Net increase (decrease) in fair value (2) 7
Unrealized gains arising during the period 4 10
Changes in unrealized gains and losses on junior subordinated debentures carried at fair value, net of taxes 3 8
Residential Mortgage Banking Revenue    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Net increase (decrease) in fair value $ 15 $ 1