Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 2,493	$ 957
Accounts receivable	1,169	1,212
Accounts receivable - related entities	3,036	5,987
Prepaid expenses	2,061	2,041
Fair value of derivative instruments	5,062	4,568
Total current assets	13,821	14,765
Oil and natural gas properties and related equipment
Oil and natural gas properties, equipment and facilities (successful efforts method)	757,825	758,913
Gathering and transportation assets	165,111	152,209
Material and supplies	1,056	1,056
Less: accumulated depreciation, depletion, amortization and impairment	(702,803)	(689,358)
Oil and natural gas properties and equipment, net	221,189	222,820
Other assets
Intangible assets, net	182,354	185,766
Fair value of derivative instruments	5,945	3,964
Equity investments	111,987	111,614
Other non-current assets	681	776
Total assets	535,977	539,705
Current liabilities
Accounts payable and accrued liabilities	883	951
Accounts payable and accrued liabilities - related entities	13,272	7,046
Royalties payable	954	706
Fair value of derivative instruments	92	740
Total current liabilities	15,201	9,443
Other liabilities
Asset retirement obligation	14,032	13,579
Long-term debt, net of debt issuance costs	158,924	151,322
Fair value of derivative instruments		1,356
Other liabilities	4,049	4,270
Total other liabilities	177,005	170,527
Total liabilities	192,206	179,970
Commitments and contingencies (See Note 11)
Mezzanine equity
Class B preferred units, 31,000,887 and 29,296,441 units issued and outstanding as of March 31, 2017 and December 31, 2016, respectively	343,395	342,991
Partners' capital
Common units, 14,153,061 and 13,447,749 units issued and outstanding as of March 31, 2017 and December 31, 2016, respectively	376	16,744
Total partners' capital	376	16,744
Total liabilities and partners' capital	$ 535,977	$ 539,705