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Stock-Based Compensation - Restricted Stock Units (Details)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2023
USD ($)
$ / shares
shares
Dec. 31, 2022
USD ($)
$ / shares
shares
Dec. 31, 2021
USD ($)
$ / shares
shares
Stock-based compensation      
Stock-based compensation expense | $ $ 9.6 $ 10.3 $ 13.1
Restricted Stock Units      
Stock-based compensation      
Ratio of common stock for each vested award 1    
Number of Shares      
Unvested as of beginning of period (in shares) | shares 263,160 185,329 43,550
Granted (in shares) | shares 232,280 169,497 198,771
Vested (in shares) | shares (122,036) (74,178) (49,519)
Forfeited (in shares) | shares (27,843) (17,488) (7,473)
Unvested as of end of period (in shares) | shares 345,561 263,160 185,329
Weighted Average Grant Date Fair Value      
Unvested as of beginning of period (in dollars per share) | $ / shares $ 27.91 $ 27.09 $ 21.93
Granted (in dollars per share) | $ / shares 25.57 28.35 27.13
Vested (in dollars per share) | $ / shares 27.75 27.18 23.08
Forfeited (in dollars per share) | $ / shares 27.38 26.80 26.37
Unvested as of end of period (in dollars per share) | $ / shares $ 26.50 $ 27.91 $ 27.09
Stock-based compensation      
Total fair value of vested shares (in dollars) | $ $ 3.4 $ 2.0 $ 1.0
Unrecognized compensation expense | $ $ 5.2 $ 4.1 $ 3.3
Period for recognition of unrecognized compensation expense 10 months 24 days    
Restricted Stock Units | Non-employee directors      
Number of Shares      
Granted (in shares) | shares 29,704 20,023 21,839
Weighted Average Grant Date Fair Value      
Granted (in dollars per share) | $ / shares $ 18.85 $ 27.66 $ 27.36
Restricted Stock Units | Employees      
Number of Shares      
Granted (in shares) | shares 202,576 149,474 176,932
Weighted Average Grant Date Fair Value      
Granted (in dollars per share) | $ / shares $ 26.28 $ 28.44 $ 27.10