FAIR VALUE MEASUREMENTS Table 1 (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Recurring Fair Value Measurements
Assets
Total (assets)	$ 14,336	$ 16,479
Liabilities [Abstract]
Total (liabilities)	(3,688)	(6,591)
Recurring Fair Value Measurements \| Fair Value Level 1
Assets
Total (assets)	11,504	11,126
Liabilities [Abstract]
Total (liabilities)	(419)	(1,388)
Recurring Fair Value Measurements \| Fair Value Level 2
Assets
Total (assets)	2,832	5,353
Liabilities [Abstract]
Total (liabilities)	(1,572)	(4,623)
Recurring Fair Value Measurements \| Fair Value Level 3
Assets
Total (assets)	0	0
Liabilities [Abstract]
Total (liabilities)	(1,697)	(580)
Recurring Fair Value Measurements \| Other current assets
Assets
Product imbalances - asset	179	117
Commodity derivatives - asset	11,402	16,362
Recurring Fair Value Measurements \| Other current assets \| Fair Value Level 1
Assets
Product imbalances - asset	179	117
Commodity derivatives - asset	11,325	11,009
Recurring Fair Value Measurements \| Other current assets \| Fair Value Level 2
Assets
Product imbalances - asset	0	0
Commodity derivatives - asset	77	5,353
Recurring Fair Value Measurements \| Other current assets \| Fair Value Level 3
Assets
Product imbalances - asset	0	0
Commodity derivatives - asset	0	0
Recurring Fair Value Measurements \| Other long-term assets, net
Assets
Interest rate swaps - asset	2,755
Recurring Fair Value Measurements \| Other long-term assets, net \| Fair Value Level 1
Assets
Interest rate swaps - asset	0
Recurring Fair Value Measurements \| Other long-term assets, net \| Fair Value Level 2
Assets
Interest rate swaps - asset	2,755
Recurring Fair Value Measurements \| Other long-term assets, net \| Fair Value Level 3
Assets
Interest rate swaps - asset	0
Recurring Fair Value Measurements \| Accrued liabilities
Liabilities [Abstract]
Product imbalances - liability	(419)	(1,388)
Commodity derivatives - liability	(120)	(4,623)
Recurring Fair Value Measurements \| Accrued liabilities \| Fair Value Level 1
Liabilities [Abstract]
Product imbalances - liability	(419)	(1,388)
Commodity derivatives - liability	0	0
Recurring Fair Value Measurements \| Accrued liabilities \| Fair Value Level 2
Liabilities [Abstract]
Product imbalances - liability	0	0
Commodity derivatives - liability	(120)	(4,623)
Recurring Fair Value Measurements \| Accrued liabilities \| Fair Value Level 3
Liabilities [Abstract]
Product imbalances - liability	0	0
Commodity derivatives - liability	0	0
Recurring Fair Value Measurements \| Other long-term liabilities
Liabilities [Abstract]
Guarantee liability	(1,697)	(580)
Interest rate swaps - liability	(1,452)
Recurring Fair Value Measurements \| Other long-term liabilities \| Fair Value Level 1
Liabilities [Abstract]
Guarantee liability	0	0
Interest rate swaps - liability	0
Recurring Fair Value Measurements \| Other long-term liabilities \| Fair Value Level 2
Liabilities [Abstract]
Guarantee liability	0	0
Interest rate swaps - liability	(1,452)
Recurring Fair Value Measurements \| Other long-term liabilities \| Fair Value Level 3
Liabilities [Abstract]
Guarantee liability	(1,697)	(580)
Interest rate swaps - liability	0
Axeon [Member]
Liabilities [Abstract]
Guarantee liability	$ (1,700)	$ (600)

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