Commitments and Contingencies - Other Commitments (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Other Commitments [Line Items]
2018	$ 110,031
2019	125,123
2020	116,975
2021	105,773
2022	102,476
Thereafter	885,139
Total	1,445,517
Drilling Rig Commitments [Member]
Other Commitments [Line Items]
2018	11,678	[1]
Total	11,678	[1]
Firm Transportation [Member]
Other Commitments [Line Items]
2018	84,167	[2]
2019	109,716	[2]
2020	109,976	[2]
2021	105,773	[2]
2022	102,476	[2]
Thereafter	885,139	[2]
Total	1,397,247	[2]
Gas Processing, Gathering, and Compression Services [Member]
Other Commitments [Line Items]
2018	14,186	[3]
2019	15,407	[3]
2020	6,999	[3]
Total	$ 36,592	[3]

[1] Drilling rig commitments -The Company had contracts for the service of two rigs, which one expires in September 2018 and one expires in October 2018 both with the option to extend. The values in the table represent the gross amounts that the Company is committed to pay and does not deduct amounts that other parties are responsible for as a result of cost sharing arrangements with working interest partners. The Company will record in its consolidated financial statements the Company’s proportionate share of costs based on its working interest, as applicable.

[2] Firm transportation -The Company has entered into firm transportation agreements with various pipelines in order to facilitate the delivery of production to market. These contracts commit the Company to transport minimum daily natural gas or NGL volumes at a negotiated rate, or pay for any deficiencies at a specified reservation fee rate. The amounts in this table represent the minimum daily volumes at the reservation fee rate. The values in the table represent the gross amounts that the Company is committed to pay and does not deduct amounts that other parties are responsible for as a result of cost sharing arrangements with working interest partners. The Company will record in its consolidated financial statements the Company’s proportionate share of costs based on its working interest.

[3] Gas processing, gathering, and compression services -Contractual commitments for gas processing, gathering and compression service agreements represent minimum commitments under long-term gas processing agreements as well as various gas compression agreements. The values in the table represent the gross amounts that the Company is committed to pay and does not deduct amounts that other parties are responsible for as a result of cost sharing arrangements with working interest partners. The Company will record in its consolidated financial statements its proportionate share of costs based on the Company’s working interest. Further, the values in the table do not include any commitments based on our amended agreement with Eureka Midstream contracted subsequent to year-end.