Nature of Operations and Basis of Presentation (Details)	1 Months Ended	9 Months Ended
Jan. 31, 2017 a	Sep. 30, 2017 a mi
Nature of Operations and Basis of Presentation
Length of pipeline to supply gas \| mi		137
Shoal Point Leases
Nature of Operations and Basis of Presentation
Area available for lease \| a	1,000	1,000

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration