Consolidation and Basis of Presentation (Policies)

12 Months Ended

Dec. 31, 2018

Policy Text Block [Abstract]

Consolidation, Policy [Policy Text Block]

Consolidated subsidiaries

Our consolidated financial statements include the accounts of our controlled subsidiaries. All significant transactions between our consolidated subsidiaries have been eliminated. Outside ownership interests in consolidated subsidiaries are reported as noncontrolling interests in the consolidated financial statements.

Proportionally consolidated assets

Our Canada segment owns undivided interests in certain natural gas gathering and processing assets, for which we record only our proportionate share of the assets on the consolidated balance sheets. The net book value of the property, plant and equipment recorded by us associated with these undivided interests is approximately $570.8 million at December 31, 2018. We serve as operator of these facilities and incur the costs of operating the facilities (recorded as operating expenses in the consolidated statements of operations) and charge the other owners, which are also customers, for their proportionate share of the costs (recorded as other revenue in the consolidated statements of operations).

Equity method investments

We own a 51% interest in White Cliffs Pipeline, LLC ("White Cliffs"), which we account for under the equity method as the other owners have substantive rights to participate in its management. White Cliffs is included in our U.S. Liquids segment.

We own an 11.78% interest in the general partner of NGL Energy Partners LP (NYSE: NGL) ("NGL Energy") which we account for under the equity method. Our investment in NGL Energy is included in Corporate and Other for segment reporting.