v3.26.3
Note 2 - Business Combinations (Details Textual)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Mar. 02, 2026
USD ($)
Sep. 30, 2026
USD ($)
Sep. 30, 2025
USD ($)
Sep. 30, 2026
USD ($)
Sep. 30, 2025
USD ($)
Mar. 31, 2026
USD ($)
Feb. 27, 2026
$ / shares
Dec. 31, 2025
USD ($)
Goodwill   $ 270,507   $ 270,507       $ 167,450
Business Combination, Acquisition-Related Cost, Expense   6,106 $ 3,123 11,782 $ 3,123      
Middlefield Banc Corp [Member]                
Business Acquisition, Equity Interests, Exchange Ratio 2.6              
Business Combination, Consideration Transferred $ 277,363              
Business Combination, Price Per Share (in dollars per share) | $ / shares             $ 12.93  
Business Combination, Separately Recognized Transaction, Acquisition-Related Cost, Expensed   3,700 0 8,500 0      
Goodwill 103,056              
Business Combination, Recognized Asset Acquired, Financial Asset, Fair Value 1,460,000              
Business Combination, Recognized Asset Acquired, Financial Asset, Gross Contractual Amount $ 1,480,000              
Business Combination, Acquisition-Related Cost, Expense   6,100 0 22,600 0      
Business Combination, Recognized Liability Assumed, Allowance for Credit Losses, Current   $ 0 $ 0 $ 0 $ 0 $ 14,800