OWNERS' EQUITY (Narrative) (Details) (USD $)	1 Months Ended		3 Months Ended		9 Months Ended			0 Months Ended		1 Months Ended	3 Months Ended
	Oct. 31, 2013	Jan. 31, 2013	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Oct. 28, 2013 Dividend Declared [Member]	Sep. 30, 2013 Common Unitholders [Member]	Jan. 31, 2013 Phantom Units [Member]	Mar. 31, 2013 Phantom Units [Member]
Stockholders Equity Note [Line Items]
Common units outstanding			42,599,080		42,599,080		42,320,707		42,599,080
Percentage of limited partnership interest					98.00%
Percentage of general partnership interest	2.00%				2.00%
Units vested		300,000								40,000
Units vested, fair value											$ 2,400,000
Contribution from general partner		300,000			334,000	5,714,000
Distribution to unitholders declared per unit			$ 0.770	$ 0.766	$ 2.307	$ 2.295		$ 0.770
Distribution to unitholders, amount								$ 38,500,000
Distribution to unitholders, record date								Nov. 07, 2013
Distribution to unitholders, payment date								Nov. 14, 2013