XML 91 R71.htm IDEA: XBRL DOCUMENT v3.10.0.1
Commitments and Contingencies - Future Minimum Annual Payments under Drilling, Lease and Other Agreements (Detail) - Office & Equipment Leases
$ in Thousands
Dec. 31, 2018
USD ($)
Operating Leased Assets [Line Items]  
2019 $ 4,597
2020 3,032
2021 3,331
2022 3,263
2023 3,036
Thereafter 13,112
Total $ 30,371