Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2019

Accounting Policies [Abstract]

Summary of Property and Equipment Including Oil and Natural Gas Properties

A summary of property and equipment including oil and natural gas properties is as follows (in thousands):

	June 30, 2019			December 31, 2018
Oil and natural gas properties:
Unproved	$	532,660		$	482,475
Proved		2,638,933			2,188,233
Gross oil and natural gas properties		3,171,593			2,670,708
Less accumulated depreciation, depletion and    amortization		(1,447,126	)		(1,380,650	)
Oil and natural gas properties, net		1,724,467			1,290,058
Other property and equipment		21,551			14,460
Less accumulated depreciation		(9,001	)		(8,160	)
Other property and equipment, net		12,550			6,300
Property and equipment, net	$	1,737,017		$	1,296,358

Summary of Revenue Disaggregated by Type

The following table illustrates the revenue disaggregated by type for the three and six months ended June 30, 2019 and 2018:

	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Revenues (in thousands)
Natural gas sales	$	94,364	$	54,409	$	176,189	$	112,892
NGL sales		19,393		18,702		40,641		38,446
Oil sales		29,672		30,146		58,427		62,103
Brokered natural gas and marketing revenue		11,989		365		21,519		373
Other revenue		122		—		261		—
Total revenues	$	155,540	$	103,622	$	297,037	$	213,814

Concentration Risk

The following table summarizes the Company’s concentration of receivables, net of allowances (if any), by product or service as of June 30, 2019 and December 31, 2018 (in thousands):

	June 30, 2019		December 31, 2018
Receivables by product or service:
Sale of oil and natural gas and related products    and services	$	70,005	$	94,107
Joint interest owners		15,941		24,830
Derivatives		2,824		372
Other		—		23
Total	$	88,770	$	119,332

Changes in Company's Asset Retirement Obligation Liability

The following table sets forth the changes in the Company’s ARO liability for the six months ended June 30, 2019 (in thousands):

	Six Months Ended June 30, 2019
Asset retirement obligations, beginning of period	$	7,110
Accretion		1,018
Additional liabilities incurred		229
Obligation for wells acquired		20,188
Obligation for wells drilled		244
Liabilities settled via plugging		(152	)
Less: current ARO portion (accrued liabilities)		(1,958	)
Asset retirement obligations, end of period	$	26,679