Derivative Financial Instruments - Summary of Open Commodity Derivative Contracts (Parenthetical) (Details)	Mar. 31, 2020 $ / MMBTU
Commodity Derivative Contract Deferred Premium Put Options \| Natural Gas
Derivative [Line Items]
Average deferred premium cost	0.13

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.

No definition available.

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