CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
REVENUE
Revenue from contracts with customers	$ 492,776	$ 594,737	$ 402,757
Gain (loss) on commodity derivative instruments	(4,955)	14,831	26,902
TOTAL REVENUE	487,821	609,568	429,659
OPERATING (INCOME) EXPENSE
Lease operating expense	17,665	18,415	17,280
Production costs and ad valorem taxes	60,533	64,364	47,474
Exploration expense	397	7,943	618
Depreciation, depletion, and amortization	109,584	122,653	114,534
General and administrative	63,353	76,712	77,574
Accretion of asset retirement obligations	1,117	1,103	1,026
(Gain) loss on sale of assets, net	0	(3)	(931)
TOTAL OPERATING EXPENSE	252,649	291,187	257,575
INCOME (LOSS) FROM OPERATIONS	235,172	318,381	172,084
OTHER INCOME (EXPENSE)
Interest and investment income	159	183	49
Interest expense	(21,435)	(20,756)	(15,694)
Other income (expense)	472	(2,248)	714
TOTAL OTHER EXPENSE	(20,804)	(22,821)	(14,931)
NET INCOME (LOSS)	214,368	295,560	157,153
Net (income) loss attributable to noncontrolling interests	0	(24)	34
Distributions on Series A redeemable preferred units	0	(25)	(3,117)
Distributions on Series B cumulative convertible preferred units	(21,000)	(21,000)	(1,925)
NET INCOME (LOSS) ATTRIBUTABLE TO THE GENERAL PARTNER AND COMMON AND SUBORDINATED UNITS SUBSEQUENT TO INITIAL PUBLIC OFFERING	193,368	274,511	152,145
ALLOCATION OF NET INCOME (LOSS):
General partner interest	0	0	0
NET INCOME (LOSS) ATTRIBUTABLE TO THE GENERAL PARTNER AND COMMON AND SUBORDINATED UNITS SUBSEQUENT TO INITIAL PUBLIC OFFERING	193,368	274,511	152,145
Common Units
ALLOCATION OF NET INCOME (LOSS):
Allocation of loss	$ 169,375	$ 154,662	$ 98,389
NET INCOME (LOSS) ATTRIBUTABLE TO LIMITED PARTNERS PER COMMON AND SUBORDINATED UNIT:
Per unit (basic) (in usd per share)	$ 1.01	$ 1.46	$ 1.01
Weighted average units outstanding, basic (in shares)	168,230,000	106,064,000	97,400,000
Per unit (diluted) (in usd per share)	$ 1.01	$ 1.45	$ 1.01
Weighted average units outstanding, diluted (in shares)	168,376,000	121,264,000	97,400,000
Subordinated Units
ALLOCATION OF NET INCOME (LOSS):
Allocation of loss	$ 23,993	$ 119,849	$ 53,756
NET INCOME (LOSS) ATTRIBUTABLE TO LIMITED PARTNERS PER COMMON AND SUBORDINATED UNIT:
Per unit (basic) (in usd per share)	$ 0.64	$ 1.25	$ 0.56
Weighted average units outstanding, basic (in shares)	37,740,000	96,099,000	95,149,000
Per unit (diluted) (in usd per share)	$ 0.64	$ 1.25	$ 0.56
Weighted average units outstanding, diluted (in shares)	37,740,000	96,346,000	95,149,000
Crude Oil
REVENUE
Revenue from contracts with customers	$ 263,678	$ 310,278	$ 169,728
Natural Gas
REVENUE
Revenue from contracts with customers	199,265	248,243	190,967
Real Estate
REVENUE
Revenue from contracts with customers	$ 29,833	$ 36,216	$ 42,062