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Incentive Compensation - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Cash Bonus, requisite service period 4 years    
Cash payments of vested units $ 0 $ 0 $ 0
Restricted Common Units      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Granted, weighted average grant date fair value (in usd per share) $ 17.09 $ 17.95 $ 18.48
Unrecognized compensation cost $ 8.5    
Period of weighted average recognition 1 year 8 months 1 day    
Fair value of units vested $ 12,700,000 $ 12,900,000 $ 25,100,000
Performance Units      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Granted, weighted average grant date fair value (in usd per share) $ 16.84 $ 17.94 $ 17.99
Unrecognized compensation cost $ 6,300,000    
Period of weighted average recognition 1 year 9 months 25 days    
Fair value of units vested $ 22,700,000 $ 1,500,000