CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 112,845	$ (745,336)	$ 284,620	$ (534,927)
Other comprehensive income:
Unrealized gains on derivative instruments, net	2,033	7,129	1,311	30,203
Reclassification of derivative losses to net income, net	2,296	2,296	6,888	6,928
Changes in benefit plan assets and benefit obligations	0	0	(821)	0
Other comprehensive loss from equity method investments	0	(2,325)	0	(10,082)
Total other comprehensive income	4,329	7,100	7,378	27,049
Comprehensive income (loss)	117,174	(738,236)	291,998	(507,878)
Less: Comprehensive income attributable to noncontrolling interests	(495)	(499)	(1,489)	(6,631)
Comprehensive income (loss) attributable to Buckeye Partners, L.P.	$ 116,679	$ (738,735)	$ 290,509	$ (514,509)

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