Net (Loss) Income Per Common Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net Income (Loss) Available to Common Stockholders, Basic [Abstract]
Net (loss) income from continuing operations	$ (417)	$ 23,952	$ (36,876)	$ 43,714
Net (income) loss attributable to noncontrolling interests in consolidated entities (continuing operations)	(191)	29	(321)	85
Income (Loss) from Continuing Operations Available to Common Unitholders	(608)	23,981	(37,197)	43,799
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	(1,260)	(2,918)	(26,408)	(7,058)
Net (loss) income attributable to common unitholders	(1,868)	21,063	(63,605)	36,741
Interest expense form SPLP Preferred Units	0	2,973	0	5,945
Net (loss) income attributable to common unitholders – assuming dilution	$ (1,868)	$ 24,036	$ (63,605)	$ 42,686
Net (loss) income per common unit – basic
Net (loss) income from continuing operations (in dollars per share)	$ (0.02)	$ 0.96	$ (1.49)	$ 1.75
Net loss from discontinued operations (in dollars per share)	(0.05)	(0.12)	(1.06)	(0.28)
Net (loss) income attributable to common unitholders (in dollars per share)	(0.07)	0.84	(2.55)	1.47
Net (loss) income per common unit – diluted
Net (loss) income from continuing operations (in dollars per share)	(0.02)	0.69	(1.49)	1.27
Net loss from discontinued operations (in dollars per share)	(0.05)	(0.08)	(1.06)	(0.18)
Net (loss) income attributable to common unitholders (in dollars per share)	$ (0.07)	$ 0.61	$ (2.55)	$ 1.09
Denominator for net income (loss) per common unit - basic (in shares)	24,958,026	24,982,728	24,989,440	24,915,446
Effect of dilutive securities:
Unvested restricted common units (in shares)	0	0	0	190
SPLP Preferred Units (in shares)	0	14,155,871	0	14,242,874
Denominator for net income per common unit - diluted (in shares)	24,958,026	39,138,599	24,989,440	39,158,510
Preferred Units
Effect of dilutive securities:
Antidilutive units excluded from computation of earnings per share (in shares)	28,803,727		30,454,112
Restricted Stock Units (RSUs)
Effect of dilutive securities:
Antidilutive units excluded from computation of earnings per share (in shares)	112,025	3,448	72,479

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