Oil and Natural Gas Properties Acquisitions - Schedule of Fair Values of the Assets Acquired (Details) - USD ($) $ in Thousands	1 Months Ended				3 Months Ended				6 Months Ended	12 Months Ended
	Sep. 30, 2017	Aug. 31, 2017	Jun. 30, 2017	Jan. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 30, 2017
Business Acquisition [Line Items]
Proved										$ 96,596	$ 40,242	$ 2,302
Unproved										383,535	$ 100,888	$ 60,994
2017 Acquisitions
Business Acquisition [Line Items]
Proved	$ 3,120	$ 3,277	$ 5,006	$ 5,135						16,538
Unproved	0	9,984	45,477	34,008						89,469
Total Fair Value	3,120	13,261	50,483	39,406						106,270
Cash	3,120	4,289	4,802	27,380	$ 39,591	$ 3,120	$ 4,802			39,591
Net working capital	0	0	0	263						263
Acquisition-Related Costs	0	107	1,481	1,162						2,750
Fair Value of Common Units Issued	0	$ 8,972	45,681	$ 12,026						66,679
East Texas
Business Acquisition [Line Items]
Unproved					2,267	19,946	13,329	$ 21,189		56,731
Cash	$ 15,205		$ 13,329		51,688	15,205	13,329	21,017		51,688			$ 2,137
Fair Value of Common Units Issued					130	$ 4,741	$ 0	$ 172		5,043
Noble Acquisition
Business Acquisition [Line Items]
Proved										68,877
Unproved										259,749
Total Fair Value										334,543
Cash					$ 334,543					334,543
Net working capital										5,917
Acquisition-Related Costs										$ 247
2016 Acquisitions
Business Acquisition [Line Items]
Proved									$ 39,735
Unproved									79,827
Total Fair Value									121,576
Cash									121,576
Net working capital									2,064
ARO									$ (50)