PARTNERS' CAPITAL AND DISTRIBUTIONS - Distributions (Details) - USD ($) $ / shares in Units, $ in Thousands			9 Months Ended
	Nov. 20, 2017	Nov. 03, 2017	Sep. 30, 2017	Sep. 30, 2016
Distributions to unitholders
Actual cash distributions			$ 529,169	$ 469,764
Limited Partners
Distributions to unitholders
Actual cash distributions			$ 531,400	$ 472,100
Distribution per LP unit (in dollars per share)			$ 3.75	$ 3.6
Forecast | Limited Partners
Distributions to unitholders
Actual cash distributions	$ 186,200
Subsequent event | Limited Partners
Distributions to unitholders
Cash distributions declared (in dollars per share)		$ 1.2625