v3.26.3
Marketable Securities - Available for Sale (Details) - USD ($)
$ in Thousands
Sep. 30, 2026
Dec. 31, 2025
Amortized cost    
Total marketable securities available-for-sale $ 1,974,633 $ 1,710,978
Gross unrealized holding gains    
Total marketable securities available-for-sale 1,115 9,703
Gross unrealized holding losses    
Total marketable securities available-for-sale (224,180) (134,299)
Fair value    
Total marketable securities available-for-sale 1,751,568 1,586,382
U.S. government and agencies    
Amortized cost    
Due after one year through five years   1,631
Due after ten years 39,019 41,673
Gross unrealized holding gains    
Due after one year through five years   11
Due after ten years 0 0
Gross unrealized holding losses    
Due after one year through five years   (13)
Due after ten years (8,492) (7,390)
Fair value    
Due after one year through five years   1,629
Due after ten years 30,527 34,283
Government-sponsored enterprises    
Amortized cost    
Due after one year through five years   1,040
Due after five years through ten years   996
Gross unrealized holding gains    
Due after one year through five years   6
Due after five years through ten years   7
Gross unrealized holding losses    
Due after one year through five years   (2)
Due after five years through ten years   0
Fair value    
Due after one year through five years   1,044
Due after five years through ten years   1,003
Municipal securities    
Amortized cost    
Due within one year 3,578 1,810
Due after one year through five years 3,299 10,876
Due after five years through ten years 21,308 25,111
Due after ten years 47,057 52,342
Gross unrealized holding gains    
Due within one year 0 9
Due after one year through five years 0 118
Due after five years through ten years 0 393
Due after ten years 87 342
Gross unrealized holding losses    
Due within one year (28) 0
Due after one year through five years (101) (7)
Due after five years through ten years (2,707) (1,253)
Due after ten years (10,475) (6,473)
Fair value    
Due within one year 3,550 1,819
Due after one year through five years 3,198 10,987
Due after five years through ten years 18,601 24,251
Due after ten years 36,669 46,211
Corporate debt issues    
Amortized cost    
Due within one year   500
Due after one year through five years 16,276 4,716
Due after five years through ten years 84,266 46,436
Due after ten years 12,000 4,000
Gross unrealized holding gains    
Due within one year   0
Due after one year through five years 107 12
Due after five years through ten years 856 1,429
Due after ten years 19 27
Gross unrealized holding losses    
Due within one year   0
Due after one year through five years (367) (22)
Due after five years through ten years (1,909) (64)
Due after ten years 0 0
Fair value    
Due within one year   500
Due after one year through five years 16,016 4,706
Due after five years through ten years 83,213 47,801
Due after ten years 12,019 4,027
Mortgage-backed securities    
Amortized cost    
Due within one year 15  
Due after one year through five years 11,405  
Due after five years through ten years 21,507  
Due after ten years 1,714,903  
Total marketable securities available-for-sale 1,747,830 1,519,847
Gross unrealized holding gains    
Total marketable securities available-for-sale 46 7,349
Gross unrealized holding losses    
Total marketable securities available-for-sale (200,101) (119,075)
Fair value    
Due within one year 15  
Due after one year through five years 10,672  
Due after five years through ten years 20,714  
Due after ten years 1,516,374  
Total marketable securities available-for-sale 1,547,775 1,408,121
Fixed rate pass-through    
Amortized cost    
Total marketable securities available-for-sale 520,098 407,377
Gross unrealized holding gains    
Total marketable securities available-for-sale 0 4,008
Gross unrealized holding losses    
Total marketable securities available-for-sale (39,689) (10,685)
Fair value    
Total marketable securities available-for-sale 480,409 400,700
Variable rate pass-through    
Amortized cost    
Total marketable securities available-for-sale 344 3,015
Gross unrealized holding gains    
Total marketable securities available-for-sale 2 66
Gross unrealized holding losses    
Total marketable securities available-for-sale 0 (2)
Fair value    
Total marketable securities available-for-sale 346 3,079
Fixed rate agency CMOs    
Amortized cost    
Total marketable securities available-for-sale 1,193,431 1,063,820
Gross unrealized holding gains    
Total marketable securities available-for-sale 10 3,170
Gross unrealized holding losses    
Total marketable securities available-for-sale (160,399) (108,309)
Fair value    
Total marketable securities available-for-sale 1,033,042 958,681
Variable rate agency CMOs    
Amortized cost    
Total marketable securities available-for-sale 33,957 45,635
Gross unrealized holding gains    
Total marketable securities available-for-sale 34 105
Gross unrealized holding losses    
Total marketable securities available-for-sale (13) (79)
Fair value    
Total marketable securities available-for-sale $ 33,978 $ 45,661