Natural Gas Producing Activities (Unaudited) - Results of Operations Related to Natural Gas, NGL and Oil Production (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reserve Quantities [Line Items]
Sales of natural gas, NGLs and oil		$ 3,791,414	$ 4,709,384
Transportation and processing		1,752,752	1,697,001	$ 1,164,783
Production		153,785	195,775	181,349
Exploration		7,223	6,765	17,565
Depreciation and depletion		1,538,745	1,569,038	970,985
Impairment/loss on sale/exchange of long-lived assets	$ 1,124,400	1,138,287	2,709,976	0
Impairment and expiration of leases		556,424	279,708	7,552
Income tax (benefit) expense		(340,843)	(454,009)	121,359
Results of operations from producing activities, excluding corporate overhead		(1,014,959)	(1,308,735)	187,725
Sales of natural gas, natural gas liquids and oil
Reserve Quantities [Line Items]
Sales of natural gas, NGLs and oil		$ 3,791,414	$ 4,695,519	$ 2,651,318

Gain (Loss) on Expiration and Impairment of Lease

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Exploration expenses (including prospecting) related to oil and gas producing entities and would be included in operating expenses of that entity. Costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: (i) Costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. (ii) Costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, and the maintenance of land and lease records. (iii) Dry hole contributions and bottom hole contributions. (iv) Costs of drilling and equipping exploratory wells. (v) Costs of drilling exploratory-type stratigraphic test wells.

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The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

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Depreciation, depletion and amortization, and valuation provisions (impairments) related to oil and gas producing activities.

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Income tax expense for oil and gas producing activities.

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The results of operations for oil and gas producing activities, excluding corporate overhead and interest costs.

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Production (lifting) costs from oil and gas producing activities, including but not limited to lease operating expense, production and ad valorem taxes, and transportation expense.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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