Regulatory Accounting	9 Months Ended
Sep. 30, 2017
Regulatory Assets and Liabilities, Other Disclosures [Abstract]
Regulatory Accounting [Text Block]	Regulatory Accounting Hurricane Harvey. NGD suffered damage as a result of Hurricane Harvey, a major storm classified as a Category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale, that first struck the Texas coast on Friday, August 25, 2017 and remained over the Houston area for the next several days. The unprecedented flooding from torrential amounts of rainfall accompanying the storm caused significant damage to or destruction of residences and businesses served by NGD. Currently, NGD estimates that total costs to restore natural gas distribution facilities damaged as a result of Hurricane Harvey will range from $25 million to $30 million and estimates that the total restoration costs covered by insurance will be approximately $17 million. NGD will defer the uninsured storm restoration costs as management believes it is probable that such costs will be recovered through traditional rate adjustment mechanisms for capital costs and through the next rate proceeding for operation and maintenance expenses. As of September 30, 2017, NGD has recorded approximately $7 million in regulatory assets, net of $2 million of insurance receivables recorded, for restoration costs incurred. As a result, storm restoration costs should not materially affect CERC’s reported net income for 2017.

Regulatory Accounting

Hurricane Harvey. NGD suffered damage as a result of Hurricane Harvey, a major storm classified as a Category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale, that first struck the Texas coast on Friday, August 25, 2017 and remained over the Houston area for the next several days. The unprecedented flooding from torrential amounts of rainfall accompanying the storm caused significant damage to or destruction of residences and businesses served by NGD.

Currently, NGD estimates that total costs to restore natural gas distribution facilities damaged as a result of Hurricane Harvey will range from $25 million to $30 million and estimates that the total restoration costs covered by insurance will be approximately $17 million. NGD will defer the uninsured storm restoration costs as management believes it is probable that such costs will be recovered through traditional rate adjustment mechanisms for capital costs and through the next rate proceeding for operation and maintenance expenses. As of September 30, 2017, NGD has recorded approximately $7 million in regulatory assets, net of $2 million of insurance receivables recorded, for restoration costs incurred. As a result, storm restoration costs should not materially affect CERC’s reported net income for 2017.