Amount which reported as a reduction in equity earnings during the year.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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EQUITY INVESTMENT IN JOINT VENTURE (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Feb. 15, 2017	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Income (loss) from equity method investments		$ 21.7	$ 28.1	$ 0.0
Reduction To Equity Earnings		$ 9.9	$ 12.8
MarEn Bakken Company LLC [Member]
Business Acquisition, Percentage of Voting Interests Acquired	49.00%
Bakken Pipeline System [Member]
Business Acquisition, Percentage of Voting Interests Acquired	49.00%
Noncontrolling interest, ownership percentage by parent (in percent)	75.00%
Noncontrolling interest, ownership percentage by noncontrolling owners	27.60%
Consideration transferred	$ 1,500.0
Goodwill	14.4
Business combination, finite-lived intangibles	$ 931.4
MarEn Bakken Company LLC [Member]
Noncontrolling interest, ownership percentage by noncontrolling owners	25.00%