Supplemental Guarantor / Non-Guarantor Financial Information Condensed Consolidating Statement of Comprehensive Income (Details) - USD ($) $ in Thousands		3 Months Ended
	Feb. 05, 2020	Mar. 31, 2020	Mar. 31, 2019
Revenues:
Revenues		$ 127,854	$ 134,497
Operating costs and expenses [Abstract]
Operations (exclusive of depreciation and amortization)		34,981	37,519
Depreciation and amortization		23,978	23,824
General and administrative		2,702	2,620
Total operating costs and expenses		61,661	63,963
Operating Income (Loss)		66,193	70,534
Equity in earnings of subsidiaries		0	0
Equity in earnings of equity method investments		1,714	2,100
Interest expense		(17,767)	(19,022)
Interest income		2,218	528
Gain (Loss) on Extinguishment of Debt	$ 25,900	(25,915)	0
Gain on sale of assets and other		506	(310)
Nonoperating Income (Expense)		(39,244)	(16,704)
Income before income taxes		26,949	53,830
State income tax benefit (expense)		(37)	(36)
Net income		26,912	53,794
Allocation of net income attributable to noncontrolling interests		(2,051)	(2,612)
Net income attributable to the partners		24,861	51,182
Parent
Revenues:
Revenues		0	0
Operating costs and expenses [Abstract]
Operations (exclusive of depreciation and amortization)		0	0
Depreciation and amortization		0
General and administrative		1,099	1,076
Total operating costs and expenses		1,099	1,076
Operating Income (Loss)		(1,099)	(1,076)
Equity in earnings of subsidiaries		68,535	71,299
Equity in earnings of equity method investments		0	0
Interest expense		(16,730)	(19,041)
Interest income		0	0
Gain (Loss) on Extinguishment of Debt		(25,915)
Gain on sale of assets and other		70	0
Nonoperating Income (Expense)		25,960	52,258
Income before income taxes		24,861	51,182
State income tax benefit (expense)		0	0
Net income		24,861	51,182
Allocation of net income attributable to noncontrolling interests		0	0
Net income attributable to the partners		24,861	51,182
Guarantor Restricted Subsidiaries
Revenues:
Revenues		113,910	119,458
Operating costs and expenses [Abstract]
Operations (exclusive of depreciation and amortization)		31,131	34,077
Depreciation and amortization		19,753	19,536
General and administrative		1,603	1,544
Total operating costs and expenses		52,487	55,157
Operating Income (Loss)		61,423	64,301
Equity in earnings of subsidiaries		4,295	5,496
Equity in earnings of equity method investments		2,088	2,100
Interest expense		(1,037)	19
Interest income		2,218	528
Gain (Loss) on Extinguishment of Debt		0
Gain on sale of assets and other		420	(329)
Nonoperating Income (Expense)		7,984	7,814
Income before income taxes		69,407	72,115
State income tax benefit (expense)		(37)	(36)
Net income		69,370	72,079
Allocation of net income attributable to noncontrolling interests		(835)	(780)
Net income attributable to the partners		68,535	71,299
Non-Guarantor Non-Restricted Subsidiaries
Revenues:
Revenues		13,944	15,039
Operating costs and expenses [Abstract]
Operations (exclusive of depreciation and amortization)		3,850	3,442
Depreciation and amortization		4,225	4,288
General and administrative		0	0
Total operating costs and expenses		8,075	7,730
Operating Income (Loss)		5,869	7,309
Equity in earnings of subsidiaries		0	0
Equity in earnings of equity method investments		(374)	0
Interest expense		0	0
Interest income		0	0
Gain (Loss) on Extinguishment of Debt		0
Gain on sale of assets and other		16	19
Nonoperating Income (Expense)		(358)	19
Income before income taxes		5,511	7,328
State income tax benefit (expense)		0	0
Net income		5,511	7,328
Allocation of net income attributable to noncontrolling interests		(1,216)	(1,832)
Net income attributable to the partners		4,295	5,496
Eliminations
Revenues:
Revenues		0	0
Operating costs and expenses [Abstract]
Operations (exclusive of depreciation and amortization)		0	0
Depreciation and amortization		0	0
General and administrative		0	0
Total operating costs and expenses		0	0
Operating Income (Loss)		0	0
Equity in earnings of subsidiaries		(72,830)	(76,795)
Equity in earnings of equity method investments		0	0
Interest expense		0	0
Interest income		0	0
Gain (Loss) on Extinguishment of Debt		0
Gain on sale of assets and other		0	0
Nonoperating Income (Expense)		(72,830)	(76,795)
Income before income taxes		(72,830)	(76,795)
State income tax benefit (expense)		0	0
Net income		(72,830)	(76,795)
Allocation of net income attributable to noncontrolling interests		0	0
Net income attributable to the partners		(72,830)	(76,795)
Affiliates
Revenues:
Revenues		101,428	103,359
Affiliates | Parent
Revenues:
Revenues		0	0
Affiliates | Guarantor Restricted Subsidiaries
Revenues:
Revenues		94,755	97,393
Affiliates | Non-Guarantor Non-Restricted Subsidiaries
Revenues:
Revenues		6,673	5,966
Affiliates | Eliminations
Revenues:
Revenues		0	0
Third parties
Revenues:
Revenues		26,426	31,138
Third parties | Parent
Revenues:
Revenues		0	0
Third parties | Guarantor Restricted Subsidiaries
Revenues:
Revenues		19,155	22,065
Third parties | Non-Guarantor Non-Restricted Subsidiaries
Revenues:
Revenues		7,271	9,073
Third parties | Eliminations
Revenues:
Revenues		$ 0	$ 0