v3.26.3
Note 2 - Business Combination (Details Textual)
$ / shares in Units, $ in Thousands
3 Months Ended 6 Months Ended 9 Months Ended
Jun. 01, 2025
USD ($)
shares
Sep. 30, 2026
USD ($)
Sep. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
Sep. 30, 2026
USD ($)
Sep. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
Jun. 01, 2026
USD ($)
Jun. 30, 2025
USD ($)
May 30, 2025
$ / shares
Dec. 31, 2024
USD ($)
Goodwill   $ 220,235   $ 220,235 $ 220,235            
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss   11,311,913   11,298,975 11,311,913            
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest   120,620 $ 156,499 154,305 120,620 $ 156,499 $ 140,149   $ 156,190   $ 82,685
Core Deposits [Member]                      
Intangible Asset, Finite-Lived, after Accumulated Amortization   51,387   59,923 51,387            
First of Long Island Corporation [Member]                      
Business Acquisition, Equity Interest Issued or Issuable, Share Exchange Ratio 0.5175                    
Business Combination, Consideration Transferred $ 270,828                    
Business Combination, Consideration Transferred, Equity Interest, Share Issued, Number of Shares (in shares) | shares 11,790,116                    
Share Price (in dollars per share) | $ / shares                   $ 22.97  
Goodwill, Measurement Period Adjustment       $ 4,600              
Goodwill $ 11,863 11,900 7,200   11,900 7,200          
Noncash Merger Related Costs   $ 0 $ 1,900   $ 2,200 $ 34,000          
First of Long Island Corporation [Member] | Financial Asset Acquired with Credit Deterioration [Member]                      
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss               $ 271,900      
Loans Receivable, Fair Value Disclosure               194,200      
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest $ 43,300                    
First of Long Island Corporation [Member] | Core Deposits [Member]                      
Intangible Asset, Finite-Lived, after Accumulated Amortization               $ 63,200      
Intangible Asset, Finite-Lived, Useful Life (Year)               10 years