Fair Value of Derivative Instruments on Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative assets	$ 233,442	$ 4,131
Derivative liabilities	103,092	23,450
Derivative assets	10,963	2,750
Derivative Liability, Noncurrent	10,689	3,385
Derivative Liability	113,781	26,835
Commodity contracts \| Current Derivative Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	233,402	4,131
Derivative liabilities	100,202	23,450
Commodity contracts \| Noncurrent Derivative Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	10,963	2,750
Derivative Liability, Noncurrent	6,789	3,385
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Derivative Liability	6,800
Interest Rate Swap \| Current Derivative Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	40	0
Derivative liabilities	2,890	0
Interest Rate Swap \| Noncurrent Derivative Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	0	0
Derivative Liability, Noncurrent	3,900	0
Fair Value, Measurements, Recurring \| Commodity contracts
Derivatives, Fair Value [Line Items]
Derivative assets	233,402	4,131
Derivative liabilities	100,202	(23,450)
Derivative assets	10,963	2,750
Derivative Liability, Noncurrent	6,789	$ 3,385
Fair Value, Measurements, Recurring \| Interest Rate Swap
Derivatives, Fair Value [Line Items]
Derivative assets	40
Derivative liabilities	2,890
Derivative assets	0
Derivative Liability, Noncurrent	$ 3,900

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
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-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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