Derivative Activities - Schedule of Additional Information Related to Master Netting Arrangements with Derivative Counterparties (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Gross Amounts of Recognized Assets	$ 74,602	$ 152,692
Gross Amounts Offset in the Balance Sheet	(34,590)	(15,138)
Net Amounts of Assets Presented in the Balance Sheet	40,012	137,554
Gross Amounts of Recognized (Liabilities)	(71,043)	(29,206)
Gross Amounts Offset in the Balance Sheet	34,590	15,138
Net Amounts of (Liabilities) Presented in the Balance Sheet	(36,453)	(14,068)
Contingent Consideration
Derivative [Line Items]
Gross Amounts of Recognized Assets	15,960
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of Assets Presented in the Balance Sheet	15,960
Commodity | Swap | Natural Gas
Derivative [Line Items]
Gross Amounts of Recognized Assets	33,559	134,364
Gross Amounts Offset in the Balance Sheet	(16,821)	(2,913)
Net Amounts of Assets Presented in the Balance Sheet	16,738	131,451
Gross Amounts of Recognized (Liabilities)	(10,120)	(1,657)
Gross Amounts Offset in the Balance Sheet	16,821	2,913
Net Amounts of (Liabilities) Presented in the Balance Sheet	6,701	1,256
Commodity | Swap | Crude Oil
Derivative [Line Items]
Gross Amounts of Recognized Assets	2,465	3,893
Gross Amounts Offset in the Balance Sheet	(829)	(4,794)
Net Amounts of Assets Presented in the Balance Sheet	1,636	(901)
Gross Amounts of Recognized (Liabilities)	(5,471)	(4,814)
Gross Amounts Offset in the Balance Sheet	829	4,794
Net Amounts of (Liabilities) Presented in the Balance Sheet	(4,642)	(20)
Commodity | Swap | N G Ls C Three Propane
Derivative [Line Items]
Gross Amounts of Recognized (Liabilities)	(8,243)
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of (Liabilities) Presented in the Balance Sheet	(8,243)
Commodity | Swap | N G Ls C Five Natural Gasoline
Derivative [Line Items]
Gross Amounts of Recognized Assets		60
Gross Amounts Offset in the Balance Sheet		(127)
Net Amounts of Assets Presented in the Balance Sheet		(67)
Gross Amounts of Recognized (Liabilities)	(4,897)	(127)
Gross Amounts Offset in the Balance Sheet	0	127
Net Amounts of (Liabilities) Presented in the Balance Sheet	(4,897)
Commodity | Swap | N G Ls N C Four Normal Butane
Derivative [Line Items]
Gross Amounts of Recognized (Liabilities)	(651)
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of (Liabilities) Presented in the Balance Sheet	(651)
Commodity | Swap | N G Ls C Four Butane
Derivative [Line Items]
Gross Amounts of Recognized Assets		167
Gross Amounts Offset in the Balance Sheet		0
Net Amounts of Assets Presented in the Balance Sheet		167
Commodity | Collars | Natural Gas
Derivative [Line Items]
Gross Amounts of Recognized Assets	7,016
Gross Amounts Offset in the Balance Sheet	(2,329)
Net Amounts of Assets Presented in the Balance Sheet	4,687
Gross Amounts of Recognized (Liabilities)	0
Gross Amounts Offset in the Balance Sheet	2,329
Net Amounts of (Liabilities) Presented in the Balance Sheet	2,329
Commodity | Collars | N G Ls C Three Propane
Derivative [Line Items]
Gross Amounts of Recognized Assets	0
Gross Amounts Offset in the Balance Sheet	(107)
Net Amounts of Assets Presented in the Balance Sheet	(107)
Gross Amounts of Recognized (Liabilities)	(3,086)
Gross Amounts Offset in the Balance Sheet	107
Net Amounts of (Liabilities) Presented in the Balance Sheet	(2,979)
Commodity | Collars | N G Ls N C Four Normal Butane
Derivative [Line Items]
Gross Amounts of Recognized (Liabilities)	(401)
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of (Liabilities) Presented in the Balance Sheet	(401)
Commodity | Three Way Collars | Natural Gas
Derivative [Line Items]
Gross Amounts of Recognized Assets	535
Gross Amounts Offset in the Balance Sheet	(6,139)
Net Amounts of Assets Presented in the Balance Sheet	(5,604)
Gross Amounts of Recognized (Liabilities)	(18,353)
Gross Amounts Offset in the Balance Sheet	6,139
Net Amounts of (Liabilities) Presented in the Balance Sheet	(12,214)
Commodity | Basis Swaps | Natural Gas
Derivative [Line Items]
Gross Amounts of Recognized Assets	7,894	10,766
Gross Amounts Offset in the Balance Sheet	(3,502)	(1,092)
Net Amounts of Assets Presented in the Balance Sheet	4,392	9,674
Gross Amounts of Recognized (Liabilities)	(4,197)	(1,371)
Gross Amounts Offset in the Balance Sheet	3,502	1,092
Net Amounts of (Liabilities) Presented in the Balance Sheet	(695)	(279)
Commodity | Spread Swaps | N G Ls C Three Propane
Derivative [Line Items]
Gross Amounts of Recognized Assets	4,863	1,913
Gross Amounts Offset in the Balance Sheet	(4,863)	(1,913)
Net Amounts of Assets Presented in the Balance Sheet	0	0
Gross Amounts of Recognized (Liabilities)	(4,069)	(16,040)
Gross Amounts Offset in the Balance Sheet	4,863	1,913
Net Amounts of (Liabilities) Presented in the Balance Sheet	794	(14,127)
Commodity | Swaption | Natural Gas
Derivative [Line Items]
Gross Amounts of Recognized Assets		0
Gross Amounts Offset in the Balance Sheet		(1,325)
Net Amounts of Assets Presented in the Balance Sheet		(1,325)
Gross Amounts of Recognized (Liabilities)	(9,803)	(2,594)
Gross Amounts Offset in the Balance Sheet	0	1,325
Net Amounts of (Liabilities) Presented in the Balance Sheet	(9,803)	(1,269)
Commodity | Swaption | Crude Oil
Derivative [Line Items]
Gross Amounts of Recognized Assets		0
Gross Amounts Offset in the Balance Sheet		(1,597)
Net Amounts of Assets Presented in the Balance Sheet		(1,597)
Gross Amounts of Recognized (Liabilities)		(2,254)
Gross Amounts Offset in the Balance Sheet		1,597
Net Amounts of (Liabilities) Presented in the Balance Sheet		(657)
Commodity | Calls | Crude Oil
Derivative [Line Items]
Gross Amounts of Recognized Assets		0
Gross Amounts Offset in the Balance Sheet		(349)
Net Amounts of Assets Presented in the Balance Sheet		(349)
Gross Amounts of Recognized (Liabilities)		(349)
Gross Amounts Offset in the Balance Sheet		349
Commodity | Calls | N G Ls C Five Natural Gasoline
Derivative [Line Items]
Gross Amounts of Recognized (Liabilities)	(546)
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of (Liabilities) Presented in the Balance Sheet	(546)
Freight
Derivative [Line Items]
Gross Amounts of Recognized Assets		1,529
Gross Amounts Offset in the Balance Sheet		(1,028)
Net Amounts of Assets Presented in the Balance Sheet		501
Freight | Swap
Derivative [Line Items]
Gross Amounts of Recognized Assets	2,310
Gross Amounts Offset in the Balance Sheet	0
Net Amounts of Assets Presented in the Balance Sheet	2,310
Gross Amounts of Recognized (Liabilities)	(1,206)
Gross Amounts Offset in the Balance Sheet	0	1,028
Net Amounts of (Liabilities) Presented in the Balance Sheet	$ (1,206)	$ 1,028