v3.25.2
Investment Securities (Narrative) (Details)
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2025
USD ($)
security
Jun. 30, 2024
USD ($)
security
Jun. 30, 2025
USD ($)
security
Jun. 30, 2024
USD ($)
security
Dec. 31, 2024
USD ($)
security
Schedule of Available-for-sale Securities [Line Items]          
Number of trading securities held | security 0   0   0
Number of securities held classified as held-to-maturity securities | security 0   0   0
Net unrealized gain on available-for-sale investment securities, net of tax | $     $ 45,200,000   $ (51,300,000)
Net unrealized gain on available-for-sale investment securities, tax | $     $ 18,200,000   21,300,000
Number of sales of available-for-sale investment securities during period | security 0 0 0 0  
Number of calls of available-for-sale investment securities during period | security 0 0 0 0  
Realized gains or losses | $ $ 0 $ 0 $ 0 $ 0  
Transfers between investment categories | $ 0 0 0 0  
Credit impairment on securities in unrealized loss position | $ 0 $ 0 0 $ 0  
Investment securities with fair value pledged at letters of credit | $ $ 23,700,000   $ 23,700,000   15,500,000
Number of investment securities were pledged to Federal Reserve or Federal Home Loan Bank | security 0   0    
Number of investment securities were pledged to secure public deposits | security 0   0    
Allowance for credit losses on available-for-sale securities | $ $ 0   $ 0   $ 0
Residential Mortgage-Backed Securities [Member]          
Schedule of Available-for-sale Securities [Line Items]          
Number of securities which were in a loss position for greater than 12 months | security 26   26