ASSET IMPAIRMENTS (Details) $ in Thousands	1 Months Ended		3 Months Ended			6 Months Ended	12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2012 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($) mi	Dec. 31, 2015 USD ($) mi	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash impairment charge							$ 0	$ 23,365	$ 169,002
Length of refined petroleum products pipelines (in miles) | mi							6,000
Asset retirement obligation	$ 3,663				$ 10,917		$ 6,823	3,663	$ 10,917
NORCO pipeline system
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Length of refined petroleum products pipelines (in miles) | mi						169
Asset retirement obligation		$ 12,100				$ 12,100
Increase (reduction) of ARO from revision of estimate due to abandonment								(3,800)
NORCO pipeline system | Domestic Pipelines & Terminals
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash asset impairment charges		$ 60,000
Natural Gas Storage
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Non-cash impairment charge	$ 2,500		$ (5,400)	$ 26,300	$ 169,000			$ 23,400