v3.26.1
Securities Available for Sale and Held to Maturity - Amortized Cost and Estimated Fair Value of Available for Sale and Held to Maturity Securities (Details) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Schedule of Available For Sale and Held to Maturity Securities [Line Items]    
Securities Available for Sale, Amortized Cost $ 1,896,135 $ 1,842,444
Securities Available for Sale, Gross Unrealized Gains 34,589 48,915
Securities Available for Sale, Gross Unrealized (Losses) (16,889) (14,529)
Securities Available for Sale, Estimated Fair Value 1,913,835 1,876,830
Securities Held to Maturity, Amortized Cost 1,159,676 1,207,454
Securities Held to Maturity, Gross Unrealized Gains 412 2,350
Securities Held to Maturity, Gross Unrealized (Losses) (33,012) (29,235)
Securities Held to Maturity, Estimated Fair Value 1,127,076 1,180,569
U.S. Treasury Securities [Member]    
Schedule of Available For Sale and Held to Maturity Securities [Line Items]    
Securities Available for Sale, Amortized Cost 219,987 205,282
Securities Available for Sale, Gross Unrealized Gains 1,902 3,666
Securities Available for Sale, Gross Unrealized (Losses) (156) 0
Securities Available for Sale, Estimated Fair Value 221,733 208,948
Securities Held to Maturity, Amortized Cost 30,804 30,615
Securities Held to Maturity, Gross Unrealized Gains 0 185
Securities Held to Maturity, Gross Unrealized (Losses) (52) 0
Securities Held to Maturity, Estimated Fair Value 30,752 30,800
U.S. Government Agency Obligations [Member]    
Schedule of Available For Sale and Held to Maturity Securities [Line Items]    
Securities Available for Sale, Amortized Cost 71,095 70,924
Securities Available for Sale, Gross Unrealized Gains 328 609
Securities Available for Sale, Gross Unrealized (Losses) (1,168) (684)
Securities Available for Sale, Estimated Fair Value 70,255 70,849
Securities Held to Maturity, Amortized Cost 0 0
Securities Held to Maturity, Gross Unrealized Gains 0 0
Securities Held to Maturity, Gross Unrealized (Losses) 0 0
Securities Held to Maturity, Estimated Fair Value 0 0
Residential Mortgage Pass-Through Securities Guaranteed by GNMA [Member]    
Schedule of Available For Sale and Held to Maturity Securities [Line Items]    
Securities Available for Sale, Amortized Cost 42,232 40,425
Securities Available for Sale, Gross Unrealized Gains 60 106
Securities Available for Sale, Gross Unrealized (Losses) (2,095) (1,996)
Securities Available for Sale, Estimated Fair Value 40,197 38,535
Securities Held to Maturity, Amortized Cost 12,733 13,154
Securities Held to Maturity, Gross Unrealized Gains 3 22
Securities Held to Maturity, Gross Unrealized (Losses) (419) (393)
Securities Held to Maturity, Estimated Fair Value 12,317 12,783
Residential Mortgage Pass-Through Securities Issued by FNMA and FHLMC [Member]    
Schedule of Available For Sale and Held to Maturity Securities [Line Items]    
Securities Available for Sale, Amortized Cost 1,203,412 1,165,292
Securities Available for Sale, Gross Unrealized Gains 24,501 33,836
Securities Available for Sale, Gross Unrealized (Losses) (12,933) (11,369)
Securities Available for Sale, Estimated Fair Value 1,214,980 1,187,759
Securities Held to Maturity, Amortized Cost 359,768 372,311
Securities Held to Maturity, Gross Unrealized Gains 337 2,070
Securities Held to Maturity, Gross Unrealized (Losses) (9,022) (7,812)
Securities Held to Maturity, Estimated Fair Value 351,083 366,569
Other Residential Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]    
Schedule of Available For Sale and Held to Maturity Securities [Line Items]    
Securities Available for Sale, Amortized Cost 0 0
Securities Available for Sale, Gross Unrealized Gains 0 0
Securities Available for Sale, Gross Unrealized (Losses) 0 0
Securities Available for Sale, Estimated Fair Value 0 0
Securities Held to Maturity, Amortized Cost 90,748 96,667
Securities Held to Maturity, Gross Unrealized Gains 0 0
Securities Held to Maturity, Gross Unrealized (Losses) (4,535) (4,233)
Securities Held to Maturity, Estimated Fair Value 86,213 92,434
Commercial Mortgage-Backed Securities Issued or Guaranteed by FNMA, FHLMC or GNMA [Member]    
Schedule of Available For Sale and Held to Maturity Securities [Line Items]    
Securities Available for Sale, Amortized Cost 359,409 360,521
Securities Available for Sale, Gross Unrealized Gains 7,798 10,698
Securities Available for Sale, Gross Unrealized (Losses) (537) (480)
Securities Available for Sale, Estimated Fair Value 366,670 370,739
Securities Held to Maturity, Amortized Cost 665,623 694,707
Securities Held to Maturity, Gross Unrealized Gains 72 73
Securities Held to Maturity, Gross Unrealized (Losses) (18,984) (16,797)
Securities Held to Maturity, Estimated Fair Value $ 646,711 $ 677,983