Reportable Segments Reportable Segments General (Details) - Pipelines	Dec. 31, 2018 km in
Segment Reporting Information [Line Items]
Pipeline Diameter \| in	12
Kilometers of Pipeline \| km	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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration