Reserve and Related Financial Data (SMOG) - Unaudited - Schedule of Proved Reserve Quantities (Details) MMcf in Thousands, MBoe in Thousands, MBbls in Thousands	12 Months Ended
	Dec. 31, 2019 MBoe MBbls MMcf	Dec. 31, 2018 MBoe MBbls MMcf	Dec. 31, 2017 MBoe MBbls MMcf
Proved Developed and Undeveloped Reserve (Energy) [Roll Forward]
Beginning balance | MBoe	26,741	19,104	13,363
Sales of minerals-in-place | MBoe	(409)	0	(1,627)
Extensions and discoveries | MBoe	4,110	3,208	3,259
Acquisitions | MBoe	7,651	7,354	4,820
Revisions of previous estimates | MBoe	(2,299)	1,508	(147)
Production | MBoe	(2,706)	(1,417)	(858)
Ending balance | MBoe	33,088	26,741	19,104
Proved reserve quantities at December 31, 2019 attributable to temporary equity | MBoe	13,289
Proved developed reserve quantities | MBoe	17,957	11,588	6,160
Proved developed reserves at December 31, 2019 attributable to temporary equity | MBoe	7,212
Proved undeveloped reserve quantities | MBoe	15,131	15,153	12,944
Proved undeveloped reserves at December 31, 2019 attributable to temporary equity | MBoe	6,077
Crude Oil (MBbl)
Proved Developed and Undeveloped Reserves [Roll Forward]
Beginning balance	12,991	8,724	7,174
Sales of minerals-in-place	(182)	0	(1,291)
Extensions and discoveries	1,997	1,765	1,548
Acquisitions	4,256	3,669	2,141
Revisions of previous estimates	(586)	390	394
Production	(1,515)	(777)	(454)
Ending balance	16,961	12,991	8,724
Proved reserve quantities at December 31, 2019 attributable to temporary equity	6,812
Proved Developed and Undeveloped Reserve (Energy) [Roll Forward]
Proved developed reserve quantities	9,924	6,067	2,804
Proved developed reserves at December 31, 2019 attributable to temporary equity	3,986
Proved undeveloped reserve quantities	7,037	6,924	5,920
Proved undeveloped reserves at December 31, 2019 attributable to temporary equity	2,826
Natural Gas (Mmcf)
Proved Developed and Undeveloped Reserves [Roll Forward]
Beginning balance | MMcf	51,796	38,401	22,991
Sales of minerals-in-place | MMcf	(697)	0	(815)
Extensions and discoveries | MMcf	7,780	5,285	6,012
Acquisitions | MMcf	13,053	13,862	9,380
Revisions of previous estimates | MMcf	(5,495)	3,245	(2,601)
Production | MMcf	(4,707)	(2,507)	(1,768)
Ending balance | MMcf	61,730	51,796	38,401
Proved reserve quantities at December 31, 2019 attributable to temporary equity | MMcf	24,792
Proved Developed and Undeveloped Reserve (Energy) [Roll Forward]
Proved developed reserve quantities | MMcf	33,232	21,735	13,028
Proved developed reserves at December 31, 2019 attributable to temporary equity | MMcf	13,346
Proved undeveloped reserve quantities | MMcf	28,498	30,061	25,373
Proved undeveloped reserves at December 31, 2019 attributable to temporary equity | MMcf	11,445
NGL (MBbl)
Proved Developed and Undeveloped Reserves [Roll Forward]
Beginning balance	5,117	3,980	2,356
Sales of minerals-in-place	(110)	0	(200)
Extensions and discoveries	817	562	709
Acquisitions	1,218	1,374	1,116
Revisions of previous estimates	(797)	577	(108)
Production	(407)	(222)	(109)
Ending balance	5,838	5,117	3,980
Proved reserve quantities at December 31, 2019 attributable to temporary equity	2,345
Proved Developed and Undeveloped Reserve (Energy) [Roll Forward]
Proved developed reserve quantities	2,494	1,898	1,185
Proved developed reserves at December 31, 2019 attributable to temporary equity	1,002
Proved undeveloped reserve quantities	3,344	3,219	2,795
Proved undeveloped reserves at December 31, 2019 attributable to temporary equity	1,343