v3.26.1
Acquisition Activity (Narrative) (Details) - USD ($)
$ in Millions
3 Months Ended
Jan. 05, 2026
Mar. 31, 2026
Dec. 31, 2025
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]      
Goodwill $ 2,300 $ 13,282 $ 10,959
Core Deposits [Member]      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]      
Core deposit intangible amortized life   10 years  
FirstBank Holding Company      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]      
Business combination, consideration transferred 4,300    
Acquisition costs   $ 98  
Goodwill 2,323    
FirstBank Holding Company | Series A Preferred Stock      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]      
Business combination, consideration transferred 4,200    
FirstBank Holding Company | Series B      
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]      
Business combination, consideration transferred $ 100