Net Income Per Unit (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
	Jul. 25, 2016	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Net loss per unit
Distribution declared (in dollars per unit)	$ 0.325
Net loss from continuing operations attributable to the limited partners:
Distribution declared		$ 12,037	$ 11,986	$ 24,009	$ 23,802
Distribution in excess of net income		(14,402)	(17,465)	(29,063)	(28,209)
Net (loss) income from continuing operations allocated to limited partners		(2,365)	(5,479)	(5,054)	(4,407)
Net loss from discontinued operations attributable to the limited partners			542	(539)	135
Net loss allocated to limited partners		$ (2,365)	$ (4,937)	$ (5,593)	$ (4,272)
Weighted average units outstanding:
Weighted average limited partner units - Basic (in shares)		36,653,371	36,506,531	36,623,114	36,449,411
Dilutive effect of unvested phantom units			459,361		238,514
Weighted average limited partner common units - diluted		36,653,371	36,965,892	36,623,114	36,687,925
Common
Net loss from continuing operations attributable to the limited partners:
Distribution declared		$ 6,147	$ 6,091	$ 12,227	$ 12,012
Distribution in excess of net income		(7,280)	(8,783)	(14,679)	(14,149)
Net (loss) income from continuing operations allocated to limited partners		(1,133)	(2,692)	(2,452)	(2,137)
Net loss from discontinued operations attributable to the limited partners			273	(272)	68
Net loss allocated to limited partners		$ (1,133)	$ (2,419)	$ (2,724)	$ (2,069)
Weighted average units outstanding:
Weighted average limited partner units - Basic (in shares)		18,528,554	18,356,902	18,497,417	18,281,786
Dilutive effect of unvested phantom units			459,361		238,514
Weighted average limited partner common units - diluted		18,528,554	18,816,263	18,497,417	18,520,300
Net income (loss) per unit:
Basic and diluted from continuing operations (in dollars per unit)		$ (0.06)	$ (0.15)	$ (0.13)	$ (0.12)
Basic and diluted from discontinued operations (in dollars per share)			0.02	(0.02)	0.01
Basic and diluted total (in dollars per unit)		$ (0.06)	$ (0.13)	$ (0.15)	$ (0.11)
Subordinated
Net loss from continuing operations attributable to the limited partners:
Distribution declared		$ 5,890	$ 5,895	$ 11,782	$ 11,790
Distribution in excess of net income		(7,122)	(8,682)	(14,384)	(14,060)
Net (loss) income from continuing operations allocated to limited partners		(1,232)	(2,787)	(2,602)	(2,270)
Net loss from discontinued operations attributable to the limited partners			269	(267)	67
Net loss allocated to limited partners		$ (1,232)	$ (2,518)	$ (2,869)	$ (2,203)
Weighted average units outstanding:
Weighted average limited partner units - Basic (in shares)		18,124,817	18,149,629	18,125,697	18,167,625
Weighted average limited partner common units - diluted		18,124,817	18,149,629	18,125,697	18,167,625
Net income (loss) per unit:
Basic and diluted from continuing operations (in dollars per unit)		$ (0.07)	$ (0.15)	$ (0.14)	$ (0.12)
Basic and diluted from discontinued operations (in dollars per share)			0.01	(0.02)	0.00
Basic and diluted total (in dollars per unit)		$ (0.07)	$ (0.14)	$ (0.16)	$ (0.12)