Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

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):

	December 31, 2019			December 31, 2018
Oil and natural gas properties:
Unproved	$	508,576		$	482,475
Proved		2,783,232			2,188,233
Gross oil and natural gas properties		3,291,808			2,670,708
Less accumulated depreciation, depletion and    amortization		(1,532,127	)		(1,380,650	)
Oil and natural gas properties, net		1,759,681			1,290,058
Other property and equipment		20,000			14,460
Less accumulated depreciation		(8,774	)		(8,160	)
Other property and equipment, net		11,226			6,300
Property and equipment, net	$	1,770,907		$	1,296,358

Schedule of Accounts Payable

A summary of accounts payable is as follows (in thousands):

	December 31, 2019		December 31, 2018
Trade payables	$	20,232	$	27,481
Royalty payables		76,642		70,019
Production & ad valorem taxes		1,025		1,811
Derivative payable		112		4,736
Other payables		21,896		12,688
Total accounts payable	$	119,907	$	116,735

Summary of Accrued Liabilities

A summary of accrued liabilities is as follows (in thousands):

	December 31, 2019		December 31, 2018
Ad valorem and production taxes	$	9,830	$	6,193
Employee compensation		9,375		6,595
Royalties		23,311		39,969
Short term derivatives		1,362		—
Other		9,988		4,152
Total accrued liabilities	$	53,866	$	56,909

Summary of Revenue Disaggregated by Type

The following table illustrates the revenue disaggregated by type for the periods indicated:

	For the Year Ended December 31,
	2019		2018		2017
Revenues (in thousands)
Natural gas sales	$	361,318	$	274,239	$	241,379
NGL sales		84,552		86,152		64,109
Oil sales		145,829		138,202		74,690
Brokered natural gas and marketing revenue		42,274		16,552		3,481
Other revenue		468		—		—
Total revenues	$	634,441	$	515,145	$	383,659

Changes in Company's Asset Retirement Obligation Liability

The following table sets forth the changes in the Company’s ARO liability for the periods indicated (in thousands):

	For the Year Ended December 31,
	2019			2018		2017
Asset retirement obligations, beginning of period	$	7,110		$	6,029	$	4,806
Accretion		2,368			663		544
Additional liabilities incurred		2,379			418		679
Obligation for wells acquired		20,188			—		—
Obligation for wells drilled		519			—		—
Liabilities settled via plugging		(723	)		—		—
Less: current ARO portion (accrued liabilities)		(1,964	)		—		—
Asset retirement obligations, end of period	$	29,877		$	7,110	$	6,029

Sales Revenue, Net [Member] | Customer Concentration Risk [Member]

Concentration Risk

The following table sets forth the Company’s major customers and associated percentage of revenue for the periods indicated:

	For the Year Ended December 31,
	2019		2018		2017
Purchaser
BP Energy Company	23%			—		—
Emera Energy Services		—		—	17%
Marathon Petroleum	20%		25%		10%
Total	43%		25%		27%

Accounts Receivable [Member] | Product Concentration Risk [Member]

Concentration Risk

The following table summarizes concentration of receivables, net of allowances, by product or service as of December 31, 2019 and December 31, 2018 (in thousands):

	December 31, 2019		December 31, 2018
Receivables by product or service:
Sale of oil and natural gas and related products    and services	$	63,730	$	94,107
Joint interest owners		12,156		24,830
Derivatives		210		372
Other		1,306		23
Total	$	77,402	$	119,332