EQUITY INVESTMENTS IN JOINT VENTURES (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	$ 360.7	$ 372.3
Texas Express Pipeline LLC [Member]
Equity Method Investment, Ownership Percentage	35.00%
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	$ 332.8	343.5
Texas Express Gathering LLC [Member]
Equity Method Investment, Ownership Percentage	35.00%
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	$ 27.9	$ 28.8

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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