Background and Basis of Presentation (Details)	12 Months Ended
Dec. 31, 2017 a mi	Jan. 31, 2017 a
Organization and Nature of Operations
Length of pipeline to supply gas \| mi	137
Shoal Point Leases
Organization and Nature of Operations
Area available for lease \| a	994	994

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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Balance Type:	na
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