Net Income (Loss) Per Common Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net Income (Loss) Available to Common Stockholders, Basic [Abstract]
Net income from continuing operations	$ 37,383	$ 23,718	$ 507	$ 67,432
Net income attributable to noncontrolling interests in consolidated entities (continuing operations)	(248)	(114)	(569)	(29)
Income (Loss) from Continuing Operations Available to Common Unitholders	37,135	23,604	(62)	67,403
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	1,140	(26,482)	(25,268)	(33,540)
Net income (loss) attributable to common unitholders	38,275	(2,878)	(25,330)	33,863
Interest expense form SPLP Preferred Units	3,083	0	0	8,918
Net income (loss) attributable to common unitholders – assuming dilution	$ 41,358	$ (2,878)	$ (25,330)	$ 42,781
Net income (loss) per common unit – basic
Net income from continuing operations (in dollars per share)	$ 1.49	$ 0.94	$ 0	$ 2.70
Net income (loss) from discontinued operations (in dollars per share)	0.05	(1.06)	(1.02)	(1.34)
Net income (loss) attributable to common unitholders (in dollars per share)	1.54	(0.12)	(1.02)	1.36
Net income (loss) per common unit – diluted
Net income from continuing operations (in dollars per share)	0.77	0.94	0	1.93
Net income (loss) from discontinued operations (in dollars per share)	0.02	(1.06)	(1.02)	(0.85)
Net income (loss) attributable to common unitholders (in dollars per share)	$ 0.79	$ (0.12)	$ (1.02)	$ 1.08
Denominator for net income (loss) per common unit - basic (in shares)	24,874,281	25,011,142	24,844,114	24,947,814
Effect of dilutive securities:
Unvested restricted common units (in shares)	66,671	0	0	755
SPLP Preferred Units (in shares)	27,126,430	0	0	14,656,244
Denominator for net income per common unit - diluted (in shares)	52,067,382	25,011,142	24,844,114	39,604,813
Preferred Units
Effect of dilutive securities:
Antidilutive units excluded from computation of earnings per share (in shares)	15,482,984		29,344,885
Restricted Stock Units (RSUs)
Effect of dilutive securities:
Antidilutive units excluded from computation of earnings per share (in shares)	1,885		22,224

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