NET INCOME PER LIMITED PARTNER UNIT (Basic and Diluted Net Income Per Limited Partner Unit) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income (loss)		$ 183.2	$ (574.6)	$ 177.7	$ 172.4	$ 112.5	$ 184.5	$ (60.5)	$ 217.8	$ (41.3)	$ 454.3	$ 740.0
Less: Net income attributable to Noncontrolling interest		79.2	(191.9)	70.3	68.8	82.0	77.8	10.0	51.3	26.4	221.1	263.3
Less: Net income (loss) attributable to Series 1 preferred unit distributions										90.0	90.0	90.0
Less: Net income (loss) attributable to Accretion of discount on Series 1 preferred units										4.7	11.2	14.9
Net income (loss) attributable to general and limited partner interests in Enbridge Energy Partners, L.P.		$ 80.3	$ (406.4)	$ 83.7	$ 80.0	$ 6.9	$ 82.1	$ (97.1)	$ 140.1	(162.4)	132.0	371.8
Incentive distributions										(21.0)	(18.9)	(39.1)
Distributed earnings										(238.4)	(234.7)	(163.9)
Total distributed earnings attributed to our common units and i-units										(813.8)	(791.4)	(731.0)
Total distributed earnings										(1,052.2)	(1,026.1)	(894.9)
Overdistributed earnings										$ (1,214.6)	$ (894.1)	$ (523.1)
Weighted average common units and i-units outstanding										348,000,000	339,100,000	328,200,000
Basic and diluted earnings per unit:
Distributed earnings per common unit and i-unit (in dollars per share)	[1]									$ 2.34	$ 2.33	$ 2.23
Overdistributed earnings per common unit and i-unit (in dollars per share)	[2]									(3.42)	(2.58)	(1.56)
Net income (loss) per common unit and i-unit (basic and diluted) (in dollars per share)	[3]									$ (1.08)	$ (0.25)	$ 0.67
Preferred Stock [Member]
Basic and diluted earnings per unit:
Anti-dilutive Preferred Units excluded (in shares)										43,201,310
General Partner [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income (loss) attributable to general and limited partner interests in Enbridge Energy Partners, L.P.										$ (796.9)	$ (31.9)	$ 38.4
Distributed earnings attributed to our General Partner										(21.0)	(20.5)	(17.3)
Class D and Class E Units [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Distributed earnings										$ (196.4)	$ (195.3)	$ (107.5)

[1] Represents the total distributed earnings to common units and i-units divided by the weighted average number of common units and i-units outstanding for the period.

[2] Represents the common units’ and i-unit’s share (98%) of distributions in excess of earnings divided by the weighted average number of common units and i-units outstanding for the period and overdistributed earnings allocated to the common units and i-units based on the distribution waterfall that is outlined in our partnership agreement.

[3] For the years ended December 31, 2016, 2015 and 2014, 43,201,310 anti-dilutive Preferred Units and 66,100,000 anti-dilutive Class D units were excluded from the if-converted method of calculating diluted earnings per unit. For the years ended December 31, 2016 and 2015, 18,114,975 anti-dilutive Class E units were excluded from the if-converted method of calculating diluted earnings per unit.