PARTNERS' CAPITAL (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended	9 Months Ended
	Apr. 27, 2017	Apr. 27, 2017	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Unamortized beneficial conversion feature discount	$ 8.5	$ 8.5
Increase in general partners' capital account		2,700.0
General Partner [Member]
Allocations from capital accounts				$ 75.3
Class D Units [Member]
Number of units waived (in shares)	66,100,000
Series 1 Preferred units [Member]
Stock redeemed or called during period, value		1,200.0
General partner distributions		$ 357.3
Common Class A [Member]
Shares issued (in dollars per share)	$ 18.66	$ 18.66
Fair value per share (in dollars per share)	$ 18.57	$ 18.57
Stock issued during period, value		$ 1,200.0
Common Class A [Member] | General Partner [Member]
Stock issued during period, new issues (in shares)		64,300,000
Class D Units [Member]
Number of units waived (in shares)			66,100,000
Common units, issued (in shares)					66,100,000
Incentive Distribution Units [Member]
Number of units waived (in shares)		1,000
Common units, issued (in shares)					1,000
Common Class F [Member]
Common units, issued (in shares)	1,000	1,000
Limited partners' contributed capital	$ 263.0	$ 263.0
Incentive distribution, distribution per unit (in dollars per share)			$ 0.35
Minimum [Member] | Common Class F [Member]
Percentage Distributed to General Partner (in percentage)			13.00%
Incentive distribution, distribution per unit (in dollars per share)			$ 0.295
Maximum [Member] | Common Class F [Member]
Percentage Distributed to General Partner (in percentage)			23.00%
Incentive distribution, distribution per unit (in dollars per share)			$ 0.35