Oil and Natural Gas Properties Acquisitions (Tables)

12 Months Ended

Dec. 31, 2017

Business Acquisition [Line Items]

Schedule of Fair Values of the Assets Acquired

	Assets Acquired								Consideration Paid
	Proved		Unproved		Net Working Capital		Total Fair Value		Cash		Fair Value of Common Units Issued		Acquisition-Related Costs1
	(in thousands)
January	$	5,135	$	34,008	$	263	$	39,406	$	27,380	$	12,026	$	1,162
June	5,006		45,477		—		50,483		4,802		45,681		1,481
August	3,277		9,984		—		13,261		4,289		8,972		107
September	3,120		—		—		3,120		3,120		—		—
Total fair value	$	16,538	$	89,469	$	263	$	106,270	$	39,591	$	66,679	$	2,750

¹ Acquisition-related costs were expensed and included in the general and administrative expense line item of the 2017 consolidated statement of operations.

Schedule of Pro Forma Information From Business Acquisition

The following table presents unaudited pro forma information for the Partnership as if the Noble Acquisition occurred on January 1, 2016.

	For the Year Ended December 31,
	2017			2016
	(in thousands, except per unit amounts)
Revenue and other income	$	468,103		$	288,772
Net income (loss)	$	178,970		$	33,264
Net income (loss) attributable to noncontrolling interests	34			12
Distributions on Series A redeemable preferred units	(3,117		)	(5,763		)
Distributions on Series B cumulative convertible preferred units	(21,000		)	(21,000		)
Net income (loss) attributable to the general partner and common and subordinated units	$	154,887		$	6,513
Allocation of net income (loss):
General partner interest	—			—
Common units	99,776			20,696
Subordinated units	55,111			(14,183		)
	$	154,887		$	6,513
Net income (loss) attributable to limited partners per common and subordinated unit:
Per common unit (basic)	$	1.02		$	0.22
Per subordinated unit (basic)	$	0.58		$	(0.15	)
Per common unit (diluted)	$	1.02		$	0.22
Per subordinated unit (diluted)	$	0.58		$	(0.15	)

Noble Acquisition

Business Acquisition [Line Items]

Schedule of Fair Values of the Assets Acquired

The following table summarizes the preliminary estimate and allocation of the fair value of the assets acquired and the acquisition-related costs.

	Assets Acquired								Cash Consideration Paid		Acquisition-Related Costs1
	Proved		Unproved		Net Working Capital		Total Fair Value
	(in thousands)
Noble Assets	$	68,877	$	259,749	$	5,917	$	334,543	$	334,543	$	247

¹ Acquisition-related costs were expensed and included in the general and administrative expense line item of the consolidated statement of operations for the year ended December 31, 2017.

East Texas

Business Acquisition [Line Items]

Schedule of Fair Values of the Assets Acquired

	Assets Acquired		Consideration Paid
	Unproved		Cash		Fair Value of Common Units Issued
	(in thousands)
Q1 2017	$	21,189	$	21,017	$	172
Q2 2017	13,329		13,329		—
Q3 2017	19,946		15,205		4,741
Q4 2017	2,267		2,137		130
Total acquired	$	56,731	$	51,688	$	5,043

2016 Acquisitions

Business Acquisition [Line Items]

Schedule of Fair Values of the Assets Acquired

The following table summarizes the fair value assigned to the properties acquired:

	Assets Acquired											Cash Consideration Paid
	Proved		Unproved		Net Working Capital		ARO			Total Fair Value
	(in thousands)
June 2016	$	39,735	$	79,827	$	2,064	$	(50	)	$	121,576	$	121,576