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Stock-Based Compensation - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Unrecognized stock-based compensation cost $ 8.7    
Unrecognized stock-based compensation cost, weighted-average period recognized 1 year 7 months 6 days    
Annual Incentive Plan and Long Term Incentive Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation expense for stock based compensation awards $ 8.5 $ 9.3 $ 8.3