Derivatives - Fair Values (Gross and Net) of Outstanding Derivatives (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Liabilities:
Total derivatives	$ 89,583	$ 4,733
Commodity Contracts \| Current assets
Assets:
Gross Amounts Recognized at Fair Value	92,943	17,799
Gross Amounts Offset in the Balance Sheet	(8,262)	(8,633)
Net Fair Value Presented on the Balance Sheet	84,681	9,166
Commodity Contracts \| Non-current assets
Assets:
Gross Amounts Recognized at Fair Value	6,341	773
Gross Amounts Offset in the Balance Sheet	(1,073)	(248)
Net Fair Value Presented on the Balance Sheet	5,268	525
Commodity Contracts \| Current liabilities
Liabilities:
Gross Amounts Recognized at Fair Value	(8,262)	(13,450)
Gross Amounts Offset in the Balance Sheet	8,262	8,633
Net Fair Value Presented on the Balance Sheet	0	(4,817)
Commodity Contracts \| Non-current liabilities
Liabilities:
Gross Amounts Recognized at Fair Value	(1,439)	(389)
Gross Amounts Offset in the Balance Sheet	1,073	248
Net Fair Value Presented on the Balance Sheet	$ (366)	$ (141)

Fair value of liability associated with 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.

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