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Stock-Based Compensation - Schedule of Compensation Expense (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Restricted Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 1.1 $ 0.9 $ 0.9
Performance Shares      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 3.3 $ 1.4 $ 1.3