FAIR VALUE (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Fair Value Measurements [Abstract]
Commodity risk management assets		$ 14
Available for sale securities	25us-gaap_AvailableForSaleSecurities	69us-gaap_AvailableForSaleSecurities
Total assets	25us-gaap_AssetsFairValueDisclosure	83us-gaap_AssetsFairValueDisclosure
Commodity risk management liability		280
Executive retirement program liability	1,309	865
Total Liabilities	1,309us-gaap_LiabilitiesFairValueDisclosure	1,145us-gaap_LiabilitiesFairValueDisclosure
Executive retirement program liability [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning of period	865
Additions and Payments	444
Revision of value	0
Ending of period	1,309
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements [Abstract]
Commodity risk management assets		0
Available for sale securities	25	69
Total assets	25	69
Commodity risk management liability		0
Executive retirement program liability	0	0
Total Liabilities	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements [Abstract]
Commodity risk management assets		14
Available for sale securities	0	0
Total assets	0	14
Commodity risk management liability		280
Executive retirement program liability	0	0
Total Liabilities	0	280
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements [Abstract]
Commodity risk management assets		0
Available for sale securities	0	0
Total assets	0	0
Commodity risk management liability		0
Executive retirement program liability	1,309	865
Total Liabilities	$ 1,309	$ 865

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Section 25

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Value of deferred revenue or cost to provide products or services, which is expected to be recognized in income or incurred after one year or beyond the normal operating cycle, if longer, resulting from customer loyalty program. Excludes liability associated with frequent flier programs. Includes liability associated with customer loyalty programs for other businesses, for example, but is not limited to, hotels, supermarkets, credit card companies, automobile rental companies, and book sellers.

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No definition available.

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Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial and nonfinancial obligations.

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Fair value as of the balance sheet date of price risk derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets on the balance sheet.

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Fair value as of the balance sheet date of price risk derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities on the balance sheet.

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