Assets Held for Sale and Discontinued Operations - Summary of Assets and Liabilities Held for Sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total current assets held for sale	$ 1,544	$ 1,047
Total noncurrent assets held for sale	3,403	9,665
Total current liabilities associated with assets held for sale	3,711	2,815
Total noncurrent liabilities associated with assets held for sale	7,150	7,013
Assets Held for Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts receivable	758	343
Other current assets	786	704
Total current assets held for sale	1,544	1,047
Proved oil and gas properties, net	3,351	9,528
Other noncurrent assets	52	137
Total noncurrent assets held for sale	3,403	9,665
Accounts payable	2,104	2,067
Accrued liabilities	1,576	570
Other current liabilities	31	178
Total current liabilities associated with assets held for sale	3,711	2,815
Asset retirement obligations	7,146	6,488
Other liabilities	4	525
Total noncurrent liabilities associated with assets held for sale	$ 7,150	$ 7,013