v3.26.1
Summary of Significant Accounting Policies - Additional Information (Details)
 12 Months Ended
Jul. 31, 2025
USD ($)
shares
Dec. 31, 2025
USD ($)
Bond
$ / shares
shares
Dec. 31, 2024
USD ($)
Bond
shares
Summary of Significant Accounting Policies [Line Items]      
Stock issued under employee stock ownership plan | shares   1,606,100  
Proceeds from isuance of common stock   $ 185,827,000  
Payments for donation $ 1,000,000    
Common Stock, Shares, Issued | shares   20,076,250 0
Common stock, outstanding | shares   20,076,250 0
Cash, FDIC insured amount   $ 250,000  
Impairment on securities   0 $ 0
Allowance for credit losses on securities   $ 0 $ 0
Number of corporate bond which issued by national financial institution | Bond   1 1
Accrued interest receivable   $ 8,537,000 $ 8,897,000
Investments in qualified affordable housing projects   $ 911,000 $ 1,200,000
Investment, Proportional Amortization Method, Elected, Statement of Financial Position [Extensible Enumeration]   Other Assets Other Assets
ACL on off-balance sheet credit exposures   $ 693,000 $ 998,000
Goodwill   11,936,000 11,936,000
Goodwill impairment   0  
Uncertain tax positions   0 0
Interest or penalties recorded   $ 0 0
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]   srt:ChiefFinancialOfficerMember  
Residential Real Estate Loans      
Summary of Significant Accounting Policies [Line Items]      
Financing receivable written down collectible amount period   180 days  
Consumer and Home Equity Loans      
Summary of Significant Accounting Policies [Line Items]      
Financing receivable contractual past due period   180 days  
Loans      
Summary of Significant Accounting Policies [Line Items]      
Accrued interest receivable   $ 6,400,000 6,300,000
Financing receivable contractual past due period   30 days  
Accrual of interest on loans discontinued period   90 days  
Federal Home Loan Bank Stock      
Summary of Significant Accounting Policies [Line Items]      
Impairment on securities   $ 0 0
Available-for-sale Securities      
Summary of Significant Accounting Policies [Line Items]      
Accrued interest receivable   $ 1,200,000 $ 1,400,000
Common Stock      
Summary of Significant Accounting Policies [Line Items]      
Common stock issued | shares   19,176,250  
Proceeds from isuance of common stock   $ 192,000  
Issuance of common shares donated to Avidia Bank Charitable Foundation, Shares | shares 900,000 900,000  
Common Stock, Shares, Issued | shares 20,076,250    
Common stock, outstanding | shares 20,076,250 20,076,250  
Common Stock | Bank's Employee Stock Ownership Plan      
Summary of Significant Accounting Policies [Line Items]      
Proceeds from isuance of common stock   $ 185,800,000  
Common Stock | Plan of Conversion      
Summary of Significant Accounting Policies [Line Items]      
Common stock issued | shares   19,176,250  
Shares issued, price per share | $ / shares   $ 10  
Stock issued under employee stock ownership plan | shares   1,606,100