Derivatives (Schedule Of Subsequent Non-designated Hedges) (Details) - Subsequent to December 31, 2018 - Apr'19- Oct'19 - Natural gas - If Nymex - Swap	2 Months Ended
Feb. 22, 2019 MMBTU $ / Unit
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Volume (Mmbtu) \| MMBTU	20,000
Swap Price \| $ / Unit	2.900

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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