Quarterly report [Sections 13 or 15(d)]

Derivatives and Hedging Activities - Additional Information (Details)

v3.26.3
Derivatives and Hedging Activities - Additional Information (Details)
3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2026
USD ($)
Sep. 30, 2026
USD ($)
Sep. 30, 2025
USD ($)
Dec. 31, 2026
USD ($)
Dec. 31, 2025
USD ($)
Derivative [Line Items]          
State of California time deposits $ 2,632,139,000 $ 2,632,139,000     $ 2,503,421,000
Derivative liability, including accrued interest   0     $ 0
Designated as Hedging Instrument | Interest Rate Swap | Cash Flow Hedging          
Derivative [Line Items]          
Notional Amount 180,000,000 180,000,000      
State of California time deposits 181,300,000 181,300,000      
Designated as Hedging Instrument | interest Rate Cap | Cash Flow Hedging          
Derivative [Line Items]          
Notional Amount $ 26,000,000 26,000,000      
Up-front premium   $ 332,000      
Variable interest rate basis three-month term SOFR        
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]        
Contractual Strike Rate | Designated as Hedging Instrument | interest Rate Cap | Cash Flow Hedging          
Derivative [Line Items]          
Percentage of interest rate 4 4      
Location, Statement of Income, Balance [Axis]: us-gaap:InterestExpenseOperating | Designated as Hedging Instrument | Interest Rate Swap | Cash Flow Hedging | Forecast          
Derivative [Line Items]          
Reduction to interest expense       $ 100,000  
Location, Statement of Income, Balance [Axis]: us-gaap:NoninterestIncomeOtherOperatingIncome          
Derivative [Line Items]          
Fee income   $ 0 $ 0