v3.25.2
Investment Securities - Narrative (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2025
USD ($)
security
position
Jun. 30, 2024
USD ($)
Jun. 30, 2025
USD ($)
security
position
Jun. 30, 2024
USD ($)
Dec. 31, 2024
USD ($)
security
position
Schedule of Held-to-maturity Securities [Line Items]          
Available for sale debt securities, at fair value $ 3,019,796,000   $ 3,019,796,000   $ 2,768,915,000
Held to maturity debt securities 308,704,000   308,704,000   327,623,000
Accrued interest on available for sale debt securities 10,500,000   10,500,000   $ 9,700,000
Investments which pay principal on periodic basis, amortized cost 2,620,000,000   2,620,000,000    
Investments which pay principal on periodic basis, fair value 2,500,000,000   2,500,000,000    
Proceeds from sales of available for sale debt securities 0 $ 568,400,000 1,670,000 $ 568,360,000  
Gain recognized on sale of securities   0 87,000 0  
Loss recognized on sale of securities   3,000,000 0 3,000,000  
Proceeds from calls on securities $ 0 0 9,600,000 0  
Gain recognized on proceeds from calls on sale of securities     0    
Loss recognized on proceeds from calls on sale of securities     $ 0    
Securities available for sale, number of securities in an unrealized loss position | position 504   504   646
Accrued interest on held to maturity debt securities $ 2,800,000   $ 2,800,000   $ 2,900,000
Proceeds from sale of held-to-maturity securities 0 0 0 0  
Held to maturity securities, proceeds from calls 5,200,000 1,200,000 10,100,000 2,400,000  
Held to maturity securities, recognized gain on calls 0 $ 0 0    
Held to maturity securities, recognized loss on calls       $ 1,200  
Held-to-maturity, debt securities, allowance $ 20,000   $ 20,000   $ 14,000
Number of securities in an unrealized loss position | security 420   420   512
AAA          
Schedule of Held-to-maturity Securities [Line Items]          
Total portfolio (as a percent)     17.00%    
AA          
Schedule of Held-to-maturity Securities [Line Items]          
Total portfolio (as a percent)     71.00%    
A          
Schedule of Held-to-maturity Securities [Line Items]          
Total portfolio (as a percent)     8.00%    
A rated or not rated          
Schedule of Held-to-maturity Securities [Line Items]          
Total portfolio (as a percent)     3.00%