v3.19.3.a.u2

QUARTERLY FINANCIAL DATA - Table - Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Data [Abstract]
Revenues	$ 399,694	$ 378,056	$ 372,445	$ 347,826	$ 374,137	$ 380,142	$ 389,256	$ 376,727	$ 1,498,021	$ 1,520,262	$ 1,444,772
Operating income (loss)	124,056	99,972	93,283	73,605	86,683	89,165	76,387	83,493	390,916	335,728	290,510
Income (loss) from continuing operations, net of tax	78,408	52,588	46,915	28,923	42,570	43,663	26,909	33,233	206,834	146,375	110,895
Income (loss) from discontinued operations, net of tax	0	(4,777)	(964)	(306,786)	(40,444)	4,473	2,490	92,900	(312,527)	59,419	37,069
Net income (loss)	$ 78,408	$ 47,811	$ 45,951	$ (277,863)	$ 2,126	$ 48,136	$ 29,399	$ 126,133	$ (105,693)	$ 205,794	$ 147,964
Basic net income (loss) per common unit
Basic net income (loss) per common unit from continuing operations	$ 0.40	$ 0.15	$ 0.11	$ (0.06)	$ 0.07	$ (3.53)	$ 0.12	$ 0.18	$ 0.60	$ (3.34)	$ 0.23
Basic net income (loss) per common unit from discontinued operations	0	(0.04)	(0.01)	(2.85)	(0.38)	0.04	0.03	0.97	(2.90)	0.57	0.41
Total net income (loss) per common unit	0.40	0.11	0.10	(2.91)	(0.31)	(3.49)	0.15	1.15	(2.30)	(2.77)	0.64
Net Income (Loss), Net of Tax, Per Outstanding Limited Partnership Unit, Diluted [Abstract]
Diluted net (loss) income per common unit from continuing operations	0.40	0.15	0.11	(0.06)	0.07	(3.53)	0.12	0.18	0.60	(3.34)	0.23
Diluted net (loss) income per common unit from discontinued operations	0.00	(0.04)	(0.01)	(2.85)	(0.38)	0.04	0.03	0.97	(2.90)	0.57	0.41
Total net income (loss) per common unit	0.40	0.11	0.10	(2.91)	(0.31)	(3.49)	0.15	1.15	(2.30)	(2.77)	0.64
Common Limited Partner [Member]
Distribution Made to Limited Partner [Line Items]
Cash distributions per unit applicable to limited partners	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 2.40	$ 2.40	$ 4.38
Quarterly Financial Data [Abstract]
Net income (loss)									$ (227,386)	$ 110,788	$ 60,610

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