v3.26.3
Stockholders' Equity (Categories of Other Comprehensive Income) (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Balance at beginning of period $ 3,003,405 $ 2,953,017 $ 3,053,829 $ 2,814,318
Other comprehensive income (loss) (137,771) 26,085 (165,117) 79,383
Balance at end of period 2,822,220 3,032,374 2,822,220 3,032,374
Accumulated Other Comprehensive Income (Loss)        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Balance at beginning of period (216,941) (231,243) (189,595) (284,541)
Other comprehensive income (loss) (137,771) 26,085 (165,117) 79,383
Balance at end of period (354,712) (205,158) (354,712) (205,158)
Unrealized Gain (Loss) on Investment Securities Available for Sale        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Balance at beginning of period (208,881) (244,195) (197,673) (300,161)
Other comprehensive income (loss) (126,413) 29,640 (137,621) 85,606
Balance at end of period (335,294) (214,555) (335,294) (214,555)
Unrealized Gain (Loss) on Derivative Instruments        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Balance at beginning of period (8,060) 12,952 8,078 15,620
Other comprehensive income (loss) (11,358) (3,555) (27,496) (6,223)
Balance at end of period $ (19,418) $ 9,397 $ (19,418) $ 9,397