PARTNERS' CAPITAL AND DISTRIBUTIONS - Distributions (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	May. 23, 2016	May. 06, 2016	Mar. 31, 2016	Mar. 31, 2015
Distributions to unitholders
Actual cash distributions			$ 154,147	$ 144,294
Limited Partners
Distributions to unitholders
Actual cash distributions			$ 154,900	$ 145,400
Distribution per LP unit (in dollars per share)			$ 1.1875	$ 1.1375
Limited Partners | Scenario, Forecast
Distributions to unitholders
Actual cash distributions	$ 157,200
Limited Partners | Subsequent event
Distributions to unitholders
Cash distributions declared (in dollars per share)		$ 1.2