XML 39 R33.htm IDEA: XBRL DOCUMENT v3.25.1
Summary of Significant Accounting Policies - Additional Information (Details)
 3 Months Ended
Mar. 01, 2025
USD ($)
shares
Jul. 26, 2024
USD ($)
$ / shares
shares
Mar. 31, 2025
USD ($)
Segment
shares
Mar. 31, 2024
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Apr. 30, 2021
shares
Significant Accounting Policies [Line Items]              
Shares issued for directors and employee stock plans (in shares) | shares   1,380,000          
Sales price per share (in dollars per share) | $ / shares   $ 25          
Issuance of common stock   $ 34,500,000 $ 172,000 $ 56,000      
Provision for credit losses on loans     13,163,000 0      
Allowance for credit loss     34,567,000 16,037,000 $ 16,552,000 $ 15,685,000  
Estimated accretable interest income     59,800,000        
Merger-related expenses     64,700,000        
Securities held to maturity, Accrued interest receivable     2,300,000   $ 2,000,000    
Shares issued for directors and employee stock plans     $ 172,000 $ 90,000      
Stock repurchased during period, shares (in shares) | shares     0        
Stock repurchase program, number of shares authorized to be repurchased (in shares) | shares             375,388
Stock repurchase program, percent of stock outstanding             5.00%
Number of days individually evaluation     60 days        
Merger PCD loans     $ 1,300,000,000        
Number of reportable segments | Segment     1        
ASU 2023-07              
Significant Accounting Policies [Line Items]              
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]     true        
Change in Accounting Principle, Accounting Standards Update, Adoption Date     Dec. 31, 2024        
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false]     true        
Fentura Financial, Inc. [Member]              
Significant Accounting Policies [Line Items]              
Shares issued for directors and employee stock plans (in shares) | shares 6,070,836            
Shares issued for directors and employee stock plans $ 193,000,000            
Non-PCD Loans [Member]              
Significant Accounting Policies [Line Items]              
Provision for credit losses on loans 12,000,000            
Loans purchased     $ 51,600,000        
Merger PCD loans $ 1,300,000,000            
PCD Loans [Member]              
Significant Accounting Policies [Line Items]              
Allowance for credit loss     4,900,000        
Loans purchased     $ 13,100,000        
Directors' Stock Purchase Plan [Member]              
Significant Accounting Policies [Line Items]              
Shares issued for directors and employee stock plans (in shares) | shares     3,301        
Shares issued for directors and employee stock plans     $ 118,000        
Employee Stock Purchase Plan [Member]              
Significant Accounting Policies [Line Items]              
Shares issued for directors and employee stock plans (in shares) | shares     2,214        
Shares issued for directors and employee stock plans     $ 54,000