v3.26.1
Investments - Summary of Gross Unrealized or Unrecognized Losses and Fair Value of Securities (Detail) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, Less Than 12 Months, Fair Value $ 739,336 $ 167,869
Total, Available-for-sale securities, Less Than 12 Months, Unrealized Loss (8,021) (753)
Total, Available-for-sale securities, 12 Months or More, Fair Value 65,303 74,729
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss (2,092) (2,135)
Total, Available-for-sale securities, Fair Value 804,639 242,598
Total, Available-for-sale securities, Unrealized Loss (10,113) (2,888)
U.S. Government Sponsored Entities [Member]    
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, Less Than 12 Months, Fair Value 0 0
Total, Available-for-sale securities, Less Than 12 Months, Unrealized Loss 0 0
Total, Available-for-sale securities, 12 Months or More, Fair Value 0 0
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss 0 0
Total, Available-for-sale securities, Fair Value 0 0
Total, Available-for-sale securities, Unrealized Loss 0 0
U.S. Treasury securities [Member]    
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, Less Than 12 Months, Fair Value 32,206 0
Total, Available-for-sale securities, Less Than 12 Months, Unrealized Loss (18) 0
Total, Available-for-sale securities, 12 Months or More, Fair Value 0 0
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss 0 0
Total, Available-for-sale securities, Fair Value 32,206 0
Total, Available-for-sale securities, Unrealized Loss (18) 0
Government-Sponsored Residential Mortgage-Backed Securities [Member]    
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, Less Than 12 Months, Fair Value 612,954 129,917
Total, Available-for-sale securities, Less Than 12 Months, Unrealized Loss (7,216) (519)
Total, Available-for-sale securities, 12 Months or More, Fair Value 26,853 28,089
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss (898) (761)
Total, Available-for-sale securities, Fair Value 639,807 158,006
Total, Available-for-sale securities, Unrealized Loss (8,114) (1,280)
Private Label Residential Mortgage-Backed Securities [Member]    
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, 12 Months or More, Fair Value 4,038 4,326
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss (72) (115)
Total, Available-for-sale securities, Fair Value 4,038 4,326
Total, Available-for-sale securities, Unrealized Loss (72) (115)
Corporate [Member]    
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, Less Than 12 Months, Fair Value 28,690 11,837
Total, Available-for-sale securities, Less Than 12 Months, Unrealized Loss (268) (73)
Total, Available-for-sale securities, 12 Months or More, Fair Value 21,251 24,225
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss (915) (1,005)
Total, Available-for-sale securities, Fair Value 49,941 36,062
Total, Available-for-sale securities, Unrealized Loss (1,183) (1,078)
Small Business Administration Loan Pools [Member]    
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, Less Than 12 Months, Fair Value 57,020 23,308
Total, Available-for-sale securities, Less Than 12 Months, Unrealized Loss (349) (52)
Total, Available-for-sale securities, 12 Months or More, Fair Value 6,721 8,629
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss (67) (72)
Total, Available-for-sale securities, Fair Value 63,741 31,937
Total, Available-for-sale securities, Unrealized Loss (416) (124)
State and Political Subdivisions [Member]    
Schedule of Investments [Line Items]    
Total, Available-for-sale securities, Less Than 12 Months, Fair Value 8,466 2,807
Total, Available-for-sale securities, Less Than 12 Months, Unrealized Loss (170) (109)
Total, Available-for-sale securities, 12 Months or More, Fair Value 6,440 9,460
Total, Available-for-sale securities, 12 Months or More, Unrealized Loss (140) (182)
Total, Available-for-sale securities, Fair Value 14,906 12,267
Total, Available-for-sale securities, Unrealized Loss $ (310) $ (291)