Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net income (loss)	$ (7,100)	$ 3,325
Adjustments to reconcile net income (loss) to cash provided by operating activities:
Depreciation, depletion and amortization	14,294	7,262
Amortization of debt issuance costs	259	246
Revisions to asset retirement obligation included in DD&A		(862)
Asset impairments	4,688	1,309
Accretion expense	498	630
Distributions from equity investments	3,684
Equity earnings in affiliate	(1,524)	(12)
Bad debt expense		35
Gain from disposition of property and equipment		(9)
Total mark-to-market on commodity derivative contracts	(9,268)	3,736
Cash settlements on commodity derivative contracts	3,378	13,028
Unit-based compensation expense	2,019	1,952
Gain on embedded derivative		(13,192)
Amortization of intangible assets	6,824	6,917
Costs for plug and abandon activities	(45)	(86)
Changes in Operating Assets and Liabilities:
Accounts receivable	(369)	313
Accounts receivable - related entities	(125)	(5,836)
Prepaid expenses	(567)	(1,414)
Other assets	(146)	659
Accounts payable and accrued liabilities	7,309	(3,128)
Accounts payable and accrued liabilities - related entities	(222)	2,634
Royalties payable	(171)	(190)
Net cash provided by operating activities	23,416	17,317
Cash flows from investing activities:
Development of oil and natural gas properties	(210)	(2,269)
Proceeds from sale of oil and natural gas properties		16
Final settlement of oil and natural gas properties acquisition	1,468
Development of gathering and transportation assets	(15,240)
Purchases of equity investments	(8,286)
Net cash used in investing activities	(22,268)	(2,253)
Cash flows from financing activities:
Payments for offering costs	(293)	(87)
Proceeds from issuance of debt	25,000	2,000
Repurchase of common units under repurchase program		(2,948)
Units tendered by employees for tax withholdings		(140)
Distributions to common unitholders	(12,044)	(3,025)
Proceeds from issuance of common units	1,290
Class B preferred unit cash distributions	(14,000)	(16,168)
Debt issuance costs	(27)	(64)
Net cash used in financing activities	(74)	(20,432)
Net increase (decrease) in cash and cash equivalents	1,074	(5,368)
Cash and cash equivalents, beginning of period	957	6,571
Cash and cash equivalents, end of period	2,031	1,203
Supplemental disclosures of cash flow information:
Change in accrued capital expenditures	8,601	1,609
Change in asset retirement obligations	195
Cash paid during the period for interest	3,458	$ 1,732
Earnout liability	$ 221