| Reconciliation of Components Used to Derive Basic and Diluted EPS | 
 The following table is a reconciliation of the components used to derive basic and diluted EPS for the periods indicated: 
  
      
       
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         | 
         | 
         | 
         | 
         | 
         | 
         | 
         | 
        
       
           | 
           | 
        Three Months Ended  | 
           | 
           | 
        Nine Months Ended  | 
           | 
        
       
           | 
           | 
        September 30,  | 
           | 
           | 
        September 30,  | 
           | 
        
       
           | 
           | 
        2024  | 
           | 
           | 
        2023  | 
           | 
           | 
        2024  | 
           | 
           | 
        2023  | 
           | 
        
       
           | 
           | 
        (dollars in thousands, except per share amounts)  | 
           | 
        
       
        Basic EPS  | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
        
       
        Net income  | 
           | 
        $  | 
        14,892  | 
           | 
           | 
        $  | 
        18,796  | 
           | 
           | 
        $  | 
        44,506  | 
           | 
           | 
        $  | 
        61,408  | 
           | 
        
       
        Less: income allocated to unvested restricted stock  | 
           | 
           | 
        131  | 
           | 
           | 
           | 
        117  | 
           | 
           | 
           | 
        352  | 
           | 
           | 
           | 
        381  | 
           | 
        
       
        Income allocated to common shares  | 
           | 
        $  | 
        14,761  | 
           | 
           | 
        $  | 
        18,679  | 
           | 
           | 
        $  | 
        44,154  | 
           | 
           | 
        $  | 
        61,027  | 
           | 
        
       
        Weighted-average shares for basic EPS  | 
           | 
           | 
        29,968,004  | 
           | 
           | 
           | 
        30,251,961  | 
           | 
           | 
           | 
        30,048,748  | 
           | 
           | 
           | 
        30,296,991  | 
           | 
        
       
        Basic EPS (1)  | 
           | 
        $  | 
        0.49  | 
           | 
           | 
        $  | 
        0.62  | 
           | 
           | 
        $  | 
        1.47  | 
           | 
           | 
        $  | 
        2.01  | 
           | 
        
       
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
        
       
        Effect of dilutive stock options and unvested performance stock units  | 
           | 
           | 
        65,675  | 
           | 
           | 
           | 
        40,911  | 
           | 
           | 
           | 
        68,521  | 
           | 
           | 
           | 
        41,687  | 
           | 
        
       
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
        
       
        Diluted EPS  | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
        
       
        Income allocated to common shares  | 
           | 
        $  | 
        14,761  | 
           | 
           | 
        $  | 
        18,679  | 
           | 
           | 
        $  | 
        44,154  | 
           | 
           | 
        $  | 
        61,027  | 
           | 
        
       
        Weighted-average shares for diluted EPS  | 
           | 
           | 
        30,033,679  | 
           | 
           | 
           | 
        30,292,872  | 
           | 
           | 
           | 
        30,117,269  | 
           | 
           | 
           | 
        30,338,678  | 
           | 
        
       
        Diluted EPS (1)  | 
           | 
        $  | 
        0.49  | 
           | 
           | 
        $  | 
        0.62  | 
           | 
           | 
        $  | 
        1.47  | 
           | 
           | 
        $  | 
        2.01  | 
           | 
        
       
  
(1)Per share amounts may not be able to be recalculated using net income and weighted-average shares presented above due to rounding. 
 
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