Condensed Consolidated Statements of Changes in Unitholders' Capital (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period	$ 1,702,169	$ 2,487,717
Adoption of new accounting guidance (ASU 2016-13)			$ (356)
Capital contributions	19,817
Repurchase and cancellation of units		(9,925)
Capital increase related to equity-based compensation	5,079	13,212
Distributions declared	(41,873)	(130,122)
Net income (loss)	(266,616)	120,198
Foreign currency translation adjustment, net of tax	(8,149)	3,708
Unitholders' capital, end of period	1,410,071	2,484,788
Paid-in Capital
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period	750,299	893,043
Capital contributions	19,817
Repurchase and cancellation of units		(7,410)
Equity reallocation between controlling and non-controlling interests	3,925	6,125
Capital increase related to equity-based compensation	3,116	6,024
Distributions declared	0
Unitholders' capital, end of period	777,157	897,782
Retained Earnings (Accumulated Deficit)
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period	51,534	100,683
Adoption of new accounting guidance (ASU 2016-13)			(220)
Distributions declared	(21,445)	(53,738)
Net income (loss)	(167,728)	47,254
Unitholders' capital, end of period	(137,859)	94,199
Accumulated Other Comprehensive Income (Loss)
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period	(3,501)	1,053
Foreign currency translation adjustment, net of tax	(5,033)	1,711
Unitholders' capital, end of period	(8,534)	2,764
Non-controlling Interests in Consolidated Subsidiaries
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period	503,253	1,092,354
Adoption of new accounting guidance (ASU 2016-13)			$ (136)
Repurchase and cancellation of units		(2,515)
Equity reallocation between controlling and non-controlling interests	(3,925)	(6,125)
Capital increase related to equity-based compensation	1,963	7,188
Distributions declared	(13,599)	(69,555)
Net income (loss)	(105,717)	66,115
Foreign currency translation adjustment, net of tax	(3,116)	1,997
Unitholders' capital, end of period	$ 378,723	$ 1,089,459
Class A Units \| Common Units
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period (in shares)	97,967	71,662
Issuance of units (in shares)		1,455
Unit exchange (in shares)	710
Cancellation of units associated with forfeitures (in shares)		(20)
Repurchase and cancellation of units (in shares)		(169)
Unitholders' capital, end of period (in shares)	98,677	72,928
Class B Units \| Common Units
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period (in shares)	61,793	85,472
Issuance of units (in shares)	24	1,020
Unit exchange (in shares)	(710)
Repurchase and cancellation of units (in shares)		(73)
Unitholders' capital, end of period (in shares)	61,107	86,419
Series A Preferred Units \| Preferred Stock
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period	$ 173,669	$ 173,669
Distributions declared	(2,981)	(2,981)
Net income (loss)	2,981	2,981
Unitholders' capital, end of period	173,669	173,669
Series B Preferred Units \| Preferred Stock
Increase (decrease) in Stockholders' Equity:
Unitholders' capital, beginning of period	226,915	226,915
Distributions declared	(3,848)	(3,848)
Net income (loss)	3,848	3,848
Unitholders' capital, end of period	$ 226,915	$ 226,915

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