v3.20.4
SERIES D CUMULATIVE CONVERTIBLE PREFERRED UNITS Narrative 2 (Details) - Series D Preferred Limited Partner [Member] - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2021
Dec. 31, 2020
Class of Stock [Line Items]    
Required amount of per unit cash dividends to permit dividend paid in kind   $ 0.635
Unpaid dividend penalty, per unit dividend increase   $ 0.048
Unpaid dividend penalty, preferred stock, conversion basis   if we fail to pay in full any Series D Preferred Unit distribution amount for three consecutive distribution periods, then until we pay such distributions in full: (i) each holder of the Series D Preferred Units may elect to convert its Series D Preferred Units into common units on a one-for-one basis, plus any unpaid Series D distributions
Unpaid dividend penalty, minimum amount of acquisitions or asset sales requiring consent   $ 50.0
Preferred Stock, Distributions, Period - June 29, 2018 to June 28, 2020 [Member]    
Class of Stock [Line Items]    
Preferred units distribution percentage   9.75%
Preferred stock, dividend rate, amount per annum   $ 57.6
Cash distributions per unit applicable to limited partners   $ 0.619
Preferred Stock, Distributions, Period - June 29, 2020 to June 28, 2023 [Member]    
Class of Stock [Line Items]    
Preferred units distribution percentage   10.75%
Preferred stock, dividend rate, amount per annum   $ 63.4
Cash distributions per unit applicable to limited partners   $ 0.682
Preferred Stock, Distributions, Period - June 29, 2023 and thereafter [Member]    
Class of Stock [Line Items]    
Preferred unit, distribution payment rate, variable description   the greater of 13.75%, or $81.1 million, per annum ($0.872 per unit per distribution period) or the distribution per common unit thereafter
Minimum [Member] | Preferred Stock, Distributions, Period - June 29, 2023 and thereafter [Member]    
Class of Stock [Line Items]    
Preferred units distribution percentage   13.75%
Preferred stock, dividend rate, amount per annum   $ 81.1
Cash distributions per unit applicable to limited partners   $ 0.872
Subsequent Event [Member]    
Class of Stock [Line Items]    
Cash distributions per unit applicable to limited partners $ 0.682