v3.26.1
Transfers of Financial Assets - Carrying Amounts of Assets Pledged as Collateral, Borrowings and Other Transactions (Details) - USD ($)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Carrying amounts of the assets pledged as collateral    
Securities for reverse repurchase agreements $ 0 $ 0
In-substance debt defeasance 0 0
FHLB    
Carrying amounts of the assets pledged as collateral    
Borrowing capacity 3,600,000 3,300,000
Asset Pledged as Collateral    
Carrying amounts of the assets pledged as collateral    
Assets pledged as collateral 10,672,034 10,652,893
Public deposits | Asset Pledged as Collateral with Right    
Carrying amounts of the assets pledged as collateral    
Assets pledged as collateral 1,591,568 1,791,182
FHLB | Asset Pledged as Collateral    
Carrying amounts of the assets pledged as collateral    
Assets pledged as collateral 5,121,384 4,891,682
Federal Reserve Bank    
Carrying amounts of the assets pledged as collateral    
Borrowing capacity 3,300,000 3,300,000
Federal Reserve Bank | Asset Pledged as Collateral    
Carrying amounts of the assets pledged as collateral    
Assets pledged as collateral $ 3,959,082 $ 3,970,029