v3.19.3.a.u2
UNIT-BASED COMPENSATION Table 1 - Information for LTIP Plans (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unit-based awards, outstanding (units) 1,456,296 1,277,480 902,911  
Compensation expense $ 37,940 $ 30,699 $ 8,727  
Restricted units, domestic employees [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unit-based awards, outstanding (units) 1,223,143 1,028,484 736,746 647,340
Compensation expense $ 9,437 $ 8,233 $ 7,881  
Restricted units, non-employee directors [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unit-based awards, outstanding (units) 61,349 59,752 27,097  
Compensation expense $ 774 $ 524 $ 251  
Restricted units, international employees [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unit-based awards, outstanding (units) 10,243 30,918 58,107  
Compensation expense $ 711 $ 1,158 $ 595  
Performance Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unit-based awards, outstanding (units) 74,439 80,690 38,865 35,373
Compensation expense $ 4,172 $ 1,889 $ 0  
Performance units awarded and outstanding 161,561 158,326 80,961 77,014
Share-based Payment Arrangement [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Compensation expense $ 22,846 $ 18,895 $ 0  
Performance units awarded and outstanding 0 0 0