Supplemental Guarantor Financial Information Supplemental Guarantor Financial Information (Balance Sheet) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
ASSETS
Current assets	$ 99,571	$ 102,004
Property, plant, and equipment, net	611,666	647,006
Investments in affiliates	0	0
Intangible and other assets, net	34,705	37,130
Intercompany receivables	0	0
Total non-current assets	646,371	684,136
Total assets	745,942	786,140
LIABILITIES AND PARTNERS' CAPITAL
Current liabilities	44,788	43,734
Amounts payable to affiliate	12,008	6,180
Long-term debt	506,771	504,090
Preferred Units	78,120	88,130
Intercompany payables	0	0
Other long-term liabilities	1,261	757
Total liabilities	642,948	642,891
Total partners' capital	102,994	143,249
Total liabilities and partners' capital	745,942	786,140
Carrying value of Senior Notes	295,900
Parent Company [Member]
ASSETS
Current assets	0	35
Property, plant, and equipment, net	0	0
Investments in affiliates	179,080	214,703
Intangible and other assets, net	0	0
Intercompany receivables	293,156	312,227
Total non-current assets	472,236	526,930
Total assets	472,236	526,965
LIABILITIES AND PARTNERS' CAPITAL
Current liabilities	3,327	8,089
Amounts payable to affiliate	0	874
Long-term debt	287,795	286,623
Preferred Units	78,120	88,130
Intercompany payables	0	0
Other long-term liabilities	0	0
Total liabilities	369,242	383,716
Total partners' capital	102,994	143,249
Total liabilities and partners' capital	472,236	526,965
Guarantor Subsidiaries [Member]
ASSETS
Current assets	77,524	74,574
Property, plant, and equipment, net	586,236	624,051
Investments in affiliates	16,472	15,112
Intangible and other assets, net	34,389	36,794
Intercompany receivables	0	0
Total non-current assets	637,097	675,957
Total assets	714,621	750,531
LIABILITIES AND PARTNERS' CAPITAL
Current liabilities	38,554	31,789
Amounts payable to affiliate	10,219	3,780
Long-term debt	218,976	217,467
Preferred Units	0	0
Intercompany payables	267,792	282,753
Other long-term liabilities	0	39
Total liabilities	535,541	535,828
Total partners' capital	179,080	214,703
Total liabilities and partners' capital	714,621	750,531
Other Subsidiaries [Member]
ASSETS
Current assets	22,047	27,395
Property, plant, and equipment, net	25,430	22,955
Investments in affiliates	0	0
Intangible and other assets, net	316	336
Intercompany receivables	0	0
Total non-current assets	25,746	23,291
Total assets	47,793	50,686
LIABILITIES AND PARTNERS' CAPITAL
Current liabilities	2,907	3,856
Amounts payable to affiliate	1,789	1,526
Long-term debt	0	0
Preferred Units	0	0
Intercompany payables	25,364	29,474
Other long-term liabilities	1,261	718
Total liabilities	31,321	35,574
Total partners' capital	16,472	15,112
Total liabilities and partners' capital	47,793	50,686
Consolidation, Eliminations [Member]
ASSETS
Current assets	0	0
Property, plant, and equipment, net	0	0
Investments in affiliates	(195,552)	(229,815)
Intangible and other assets, net	0	0
Intercompany receivables	(293,156)	(312,227)
Total non-current assets	(488,708)	(542,042)
Total assets	(488,708)	(542,042)
LIABILITIES AND PARTNERS' CAPITAL
Current liabilities	0	0
Amounts payable to affiliate	0	0
Long-term debt	0	0
Preferred Units	0	0
Intercompany payables	(293,156)	(312,227)
Other long-term liabilities	0	0
Total liabilities	(293,156)	(312,227)
Total partners' capital	(195,552)	(229,815)
Total liabilities and partners' capital	$ (488,708)	$ (542,042)