CONSOLIDATED STATEMENTS OF PARTNERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Limited Partners’ Equity	General Partner’s Equity	Special L.P. Interests	Accumulated Other Comprehensive Income (Loss)
Beginning balance, units (in shares) at Dec. 31, 2017		56,359
Beginning balance, value at Dec. 31, 2017	$ 82,946	$ 81,589	$ 0	$ 5,290	$ (3,933)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	126,653	126,652	1
Partnership distribution declared	(203,199)	$ (203,197)	(2)
Issuance of limited partnership units related to compensation (in shares)		205
Issuance of limited partnership units related to compensation	2,940	$ 2,940
Tax effect of units involved in treasury unit transactions	(2,530)	(2,530)
Foreign currency translation	17,240				17,240
Cash flow hedging derivative activity, net of tax $(1,094)	8,366				8,366
Reclassification of stranded tax effect	0	$ 391			(391)
Ending balance, units (in shares) at Dec. 31, 2018		56,564
Ending balance, value at Dec. 31, 2018	32,416	$ 5,845	(1)	5,290	21,282
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	172,365	172,363	2
Partnership distribution declared	(210,011)	$ (210,009)	(2)
Issuance of limited partnership units related to compensation (in shares)		102
Issuance of limited partnership units related to compensation	8,183	$ 8,183
Tax effect of units involved in treasury unit transactions	(1,383)	$ (1,383)
Foreign currency translation	(11,536)				(11,536)
Cash flow hedging derivative activity, net of tax $(1,094)	0
Ending balance, units (in shares) at Dec. 31, 2019		56,666
Ending balance, value at Dec. 31, 2019	(9,966)	$ (25,001)	(1)	5,290	9,746
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	(590,243)	(590,237)	(6)
Partnership distribution declared	(53,020)	$ (53,020)	0
Issuance of limited partnership units related to compensation (in shares)		40
Issuance of limited partnership units related to compensation	(4,721)	$ (4,721)
Tax effect of units involved in treasury unit transactions	(1,490)	(1,490)
Foreign currency translation	(7,147)				(7,147)
Cash flow hedging derivative activity, net of tax $(1,094)	0
Other	150	$ 150
Ending balance, units (in shares) at Dec. 31, 2020		56,706
Ending balance, value at Dec. 31, 2020	$ (666,437)	$ (674,319)	$ (7)	$ 5,290	$ 2,599