CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
CURRENT ASSETS
Cash and cash equivalents	$ 8,119	$ 5,414
Accounts receivable	78,214	113,148
Commodity derivative assets	14,790	37,970
Prepaid expenses and other current assets	1,168	1,001
TOTAL CURRENT ASSETS	102,291	157,533
Property, Plant and Equipment [Abstract]
Oil and natural gas properties, at cost, using the successful efforts method of accounting, includes unproved properties of $1,073,447 and $1,063,883 at December 31, 2019 and 2018, respectively	3,302,340	3,441,188
Accumulated depreciation, depletion, amortization, and impairment	(1,870,412)	(1,865,692)
Oil and natural gas properties, net	1,431,928	1,575,496
Other property and equipment, net of accumulated depreciation of $11,622 and $11,048 at December 31, 2019 and 2018, respectively	2,300	385
NET PROPERTY AND EQUIPMENT	1,434,228	1,575,881
DEFERRED CHARGES AND OTHER LONG-TERM ASSETS	8,689	16,710
TOTAL ASSETS	1,545,208	1,750,124
CURRENT LIABILITIES
Accounts payable	5,309	4,149
Accrued liabilities	22,702	60,089
Commodity derivative liabilities	159	0
Other current liabilities	1,633	528
TOTAL CURRENT LIABILITIES	29,803	64,766
LONG-TERM LIABILITIES
Credit facility	394,000	410,000
Accrued incentive compensation	2,110	1,813
Commodity derivative liabilities	18	0
Asset retirement obligations	15,653	14,948
Other long-term liabilities	6,820	55,973
TOTAL LIABILITIES	448,404	547,500
COMMITMENTS AND CONTINGENCIES (Note 11)
MEZZANINE EQUITY
Temporary equity attributable to parent	298,361	298,361
EQUITY
Partners' equity — general partner interest	0	0
TOTAL EQUITY	798,443	904,263
TOTAL LIABILITIES, MEZZANINE EQUITY, AND EQUITY	1,545,208	1,750,124
Series B Cumulative Convertible Preferred Units
MEZZANINE EQUITY
Temporary equity attributable to parent	298,361	298,361
Common Units
EQUITY
Partners' equity - units	798,443	714,823
Subordinated Units
EQUITY
Partners' equity - units	$ 0	$ 189,440