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Equity Based Compensation (Summary of Performance Contingent Unit Activity) (Details) - shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Performance Shares [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Other Increases (Decreases) in Period (67,847)  
Outstanding, Number, Beginning Balance 325,851  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures 175,047  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period 138,785 248,789
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period 3,137  
Outstanding, Number, Ending Balance 291,129 [1] 325,851
Restricted Stock Units (RSUs) [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Other Increases (Decreases) in Period 0  
Outstanding, Number, Beginning Balance 62,194  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures 37,135  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period 20,232  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period 2,707  
Outstanding, Number, Ending Balance 76,390 [1] 62,194
[1] Amount outstanding at December 31, 2020, includes the amount of shares to be issued under RSUs expected to vest and number of shares to be issued under PCUs at target performance. The PCU amount of shares do not reflect potential increases or decreases that may result from the performance factor, except for the 2018 – 2020 PCU grants, which vested as of December 31, 2020.