Supplemental Disclosures of Cash Flow Information - Supplemental Cash Flow Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Supplemental Cash Flow Information [Abstract]
Cash paid for interest	$ 29,168	$ 25,746
Cash paid for income taxes	0	0
Cash paid for operating leases	970	0
Operating leases	14,955	0
Non-cash investing and financing activities:
Accounts payable and accrued liabilities - oil and gas properties	44,970	101,838
Accrued liabilities - financing costs	0	215
Change in asset retirement obligations, net of disposals	(5,443)	9,885
Retirement of treasury stock	(1,725)	(1,533)
Properties exchanged in non-cash transactions	4,561	0
Issuance of common stock for Merger	$ 0	$ 484,000