Segment Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020		Sep. 30, 2019		Dec. 31, 2019
Segment Reporting Information
Midstream Services — Affiliate		$ 88,954	$ 112,224	$ 296,477		$ 313,296
Total Revenues		187,365	181,674	557,360		513,036
Goodwill Impairment	$ 109,700	0	0	109,734		0
Income (Loss) Before Income Taxes		38,902	71,698	52,267		197,292
Additions to Long-Lived Assets		9,298	62,254	62,023		198,547
Additions to Investments		43,555	86,757	294,281	[1]	501,344	[1]
Total Assets		3,042,772		3,042,772				$ 2,926,082
Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		22,238	20,580	73,133		66,218
Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		76,173	48,870	187,750		133,522
Gathering Systems
Segment Reporting Information
Midstream Services — Affiliate		80,534	91,377	254,158		246,495
Total Revenues		177,317	158,695	507,428		437,840
Goodwill Impairment				109,734
Income (Loss) Before Income Taxes		59,703	67,419	76,877		173,747
Additions to Long-Lived Assets		9,204	57,309	61,672		191,697
Additions to Investments		0	0	0		0
Total Assets		2,031,541		2,031,541				2,160,026
Gathering Systems | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		20,610	18,448	65,520		57,823
Gathering Systems | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		76,173	48,870	187,750		133,522
Fresh Water Delivery
Segment Reporting Information
Midstream Services — Affiliate		8,420	20,847	42,319		66,801
Total Revenues		10,048	22,979	49,932		75,196
Goodwill Impairment				0
Income (Loss) Before Income Taxes		9,479	18,825	42,258		55,655
Additions to Long-Lived Assets		0	4,646	0		6,040
Additions to Investments		0	0	0		0
Total Assets		101,525		101,525				91,840
Fresh Water Delivery | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		1,628	2,132	7,613		8,395
Fresh Water Delivery | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		0	0	0		0
Investments in Midstream Entities
Segment Reporting Information
Midstream Services — Affiliate		0	0	0		0
Total Revenues		0	0	0		0
Goodwill Impairment				0
Income (Loss) Before Income Taxes		(18,068)	(5,621)	(26,207)		(5,028)
Additions to Long-Lived Assets		0	0	0		0
Additions to Investments		43,555	86,757	294,281		501,344
Total Assets		899,468		899,468				660,778
Investments in Midstream Entities | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		0	0	0		0
Investments in Midstream Entities | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		0	0	0		0
Corporate
Segment Reporting Information
Midstream Services — Affiliate		0	0	0		0
Total Revenues		0	0	0		0
Goodwill Impairment				0
Income (Loss) Before Income Taxes		(12,212)	(8,925)	(40,661)		(27,082)
Additions to Long-Lived Assets		94	299	351		810
Additions to Investments		0	0	0		0
Total Assets		10,238		10,238				$ 13,438
Corporate | Midstream Services — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		0	0	0		0
Corporate | Crude Oil Sales — Third Party
Segment Reporting Information
Services and Sales Revenues - Third Party		$ 0	$ 0	$ 0		$ 0

[1] See Note 2. Basis of Presentation for our discussion of the EPIC Y-Grade loan conversion and the reconciliation of total cash.