DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Hedge Ineffectiveness
Ineffectiveness excluding the time value component on fair value hedging instruments, net gain (loss) in income:
Ineffectiveness excluding the time value component on fair value hedging instruments	$ 425	$ 2,245	$ (80)	$ (1,232)
Derivatives NOT Designated as Hedging Instruments | Product sales | Physical Fixed Price Derivative Contracts
Gains (losses), derivative instruments
Gains (losses) on derivative instruments recognized in income	(6,851)	(9,153)	(3,475)	(6,255)
Derivatives NOT Designated as Hedging Instruments | Product sales | Physical Index Derivative Contracts
Gains (losses), derivative instruments
Gains (losses) on derivative instruments recognized in income	(13)	678	1,096	1,038
Derivatives NOT Designated as Hedging Instruments | Cost of product sales and natural gas storage services | Physical Fixed Price Derivative Contracts
Gains (losses), derivative instruments
Gains (losses) on derivative instruments recognized in income	4,736	813	4,291	210
Derivatives NOT Designated as Hedging Instruments | Cost of product sales and natural gas storage services | Physical Index Derivative Contracts
Gains (losses), derivative instruments
Gains (losses) on derivative instruments recognized in income	(113)	(1,014)	(657)	(1,053)
Derivatives NOT Designated as Hedging Instruments | Cost of product sales and natural gas storage services | Refined products | Futures Contracts
Gains (losses), derivative instruments
Gains (losses) on derivative instruments recognized in income	(1,190)	1,304	4,607	6,635
Derivatives Designated as Hedging Instruments | Cost of product sales and natural gas storage services | Hedge Ineffectiveness
Ineffectiveness excluding the time value component on fair value hedging instruments, net gain (loss) in income:
Fair value hedge ineffectiveness (excluding time value)	2,902	(249)	(725)	(809)
Time value excluded from hedge assessment	(2,477)	2,494	645	(423)
Derivatives Designated as Hedging Instruments | Cost of product sales and natural gas storage services | Refined products
Derivatives designated as fair value hedging instruments:
Physical inventory - hedged items	2,114	21,307	(7,326)	32,464
Derivatives Designated as Hedging Instruments | Cost of product sales and natural gas storage services | Refined products | Futures Contracts
Derivatives designated as fair value hedging instruments:
Future contracts for refined petroleum products	$ (1,689)	$ (19,062)	$ 7,246	$ (33,697)