CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	$ 214,368	$ 295,560	$ 157,153
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion, and amortization	109,584	122,653	114,534
Accretion of asset retirement obligations	1,117	1,103	1,026
Amortization of deferred charges	1,041	905	877
(Gain) loss on commodity derivative instruments	4,955	(14,831)	(26,902)
Net cash (paid) received on settlement of commodity derivative instruments	27,862	(38,235)	15,211
Equity-based compensation	20,484	30,134	33,044
Exploratory dry hole expense	3	6,785	0
Deferred rent	0	1,283	0
(Gain) loss on sale of assets, net	0	(3)	(931)
Changes in operating assets and liabilities:
Accounts receivable	35,044	(31,531)	(6,084)
Prepaid expenses and other current assets	(167)	210	(177)
Accounts payable, accrued liabilities, and other	(1,191)	11,474	(5,671)
Settlement of asset retirement obligations	(380)	(129)	(228)
NET CASH PROVIDED BY OPERATING ACTIVITIES	412,720	385,378	281,852
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisitions of oil and natural gas properties	(43,051)	(124,081)	(425,667)
Additions to oil and natural gas properties	(64,782)	(166,970)	(55,842)
Payments To Acquire Oil And Gas Leasehold Costs	(980)	(6,263)	(2,806)
Purchases of other property and equipment	(2,488)	(21)	(207)
Proceeds from the sale of oil and natural gas properties	1,174	9,009	11,102
Proceeds from farmouts of oil and natural gas properties	61,504	124,522	19,171
NET CASH USED IN INVESTING ACTIVITIES	(48,623)	(163,804)	(454,249)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from issuance of common units, net of offering costs	(43)	40,537	32,458
Proceeds from issuance of Series B cumulative convertible preferred units, net of offering costs	0	0	293,469
Distributions to noncontrolling interests	0	(211)	(120)
Distributions equivalents paid	(2,981)	0	0
Redemption of Series A redeemable preferred units	0	(2,115)	(19,704)
Purchase of noncontrolling interests	0	(1,706)	0
Borrowings under credit facility	334,500	373,500	292,500
Repayments under credit facility	(350,500)	(351,500)	(220,500)
Debt issuance costs and other	0	(1,242)	(3,075)
NET CASH (USED IN) PROVIDED BY FINANCING ACTIVITIES	(361,392)	(221,802)	168,267
NET CHANGE IN CASH AND CASH EQUIVALENTS	2,705	(228)	(4,130)
Cash and cash equivalents — beginning of the year	5,414	5,642	9,772
Cash and cash equivalents — end of the year	8,119	5,414	5,642
SUPPLEMENTAL DISCLOSURE
Interest paid	20,470	19,761	14,761
Common and Subordinated Units
CASH FLOWS FROM FINANCING ACTIVITIES
Distributions to unitholders	(304,439)	(250,121)	(194,799)
Repurchases of equity units	(16,929)	(10,579)	(8,185)
Preferred Units
CASH FLOWS FROM FINANCING ACTIVITIES
Distributions to unitholders	0	(690)	(3,777)
Series B Cumulative Convertible Preferred Units | Preferred Units
CASH FLOWS FROM FINANCING ACTIVITIES
Distributions to unitholders	$ (21,000)	$ (17,675)	$ 0