v3.26.1
INVESTMENT SECURITIES - Summary of Amortized Cost and Approximate Fair Value of Investment Securities (Detail) - USD ($)
Jun. 30, 2026
Dec. 31, 2025
Schedule of Held-to-Maturity Securities [Line Items]    
Amortized Cost $ 631,594,000 $ 729,134,000
Allowance for Credit Losses 0 0
Net Carrying Value 631,594,000 729,134,000
Gross Unrealized Gains 3,000 678,000
Gross Unrealized Losses (56,049,000) (46,214,000)
Fair Value 575,548,000 683,598,000
Debt securities, held to maturity, accrued interest 1,200,000 1,500,000
Asset-backed securities    
Schedule of Held-to-Maturity Securities [Line Items]    
Amortized Cost 181,633,000 258,371,000
Allowance for Credit Losses 0 0
Net Carrying Value 181,633,000 258,371,000
Gross Unrealized Gains 3,000 678,000
Gross Unrealized Losses (3,425,000) (2,432,000)
Fair Value 178,211,000 256,617,000
Agency-guaranteed residential mortgage-backed securities    
Schedule of Held-to-Maturity Securities [Line Items]    
Amortized Cost 6,622,000 6,708,000
Allowance for Credit Losses 0 0
Net Carrying Value 6,622,000 6,708,000
Gross Unrealized Gains 0 0
Gross Unrealized Losses (758,000) (718,000)
Fair Value 5,864,000 5,990,000
Agency-guaranteed commercial mortgage-backed securities    
Schedule of Held-to-Maturity Securities [Line Items]    
Amortized Cost 1,645,000 1,687,000
Allowance for Credit Losses 0 0
Net Carrying Value 1,645,000 1,687,000
Gross Unrealized Gains 0 0
Gross Unrealized Losses (239,000) (238,000)
Fair Value 1,406,000 1,449,000
Agency-guaranteed residential collateralized mortgage obligations    
Schedule of Held-to-Maturity Securities [Line Items]    
Amortized Cost 146,909,000 153,662,000
Allowance for Credit Losses 0 0
Net Carrying Value 146,909,000 153,662,000
Gross Unrealized Gains 0 0
Gross Unrealized Losses (13,485,000) (10,629,000)
Fair Value 133,424,000 143,033,000
Agency-guaranteed commercial collateralized mortgage obligations    
Schedule of Held-to-Maturity Securities [Line Items]    
Amortized Cost 190,374,000 182,272,000
Allowance for Credit Losses 0 0
Net Carrying Value 190,374,000 182,272,000
Gross Unrealized Gains 0 0
Gross Unrealized Losses (28,243,000) (22,242,000)
Fair Value 162,131,000 160,030,000
Private label collateralized mortgage obligations    
Schedule of Held-to-Maturity Securities [Line Items]    
Amortized Cost 104,411,000 126,434,000
Allowance for Credit Losses 0 0
Net Carrying Value 104,411,000 126,434,000
Gross Unrealized Gains 0 0
Gross Unrealized Losses (9,899,000) (9,955,000)
Fair Value $ 94,512,000 $ 116,479,000