Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Fair Value Measurements [Abstract]
Fair value and carrying value of debt	$ 6,000
Fair Value Measurements [Abstract]
Available for sale securities	30	$ 25
Total assets	30	25
Commodity risk management liability	335
Executive retirement program liability	1,190	1,309
Total liabilities	1,525	1,309
(Level 1) [Member]
Fair Value Measurements [Abstract]
Available for sale securities	30	25
Total assets	30	25
Commodity risk management liability	0
Executive retirement program liability	0	0
Total liabilities	0	0
(Level 2) [Member]
Fair Value Measurements [Abstract]
Available for sale securities	0	0
Total assets	0	0
Commodity risk management liability	335
Executive retirement program liability	0	0
Total liabilities	335	0
(Level 3) [Member]
Fair Value Measurements [Abstract]
Available for sale securities	0	0
Total assets	0	0
Commodity risk management liability	0
Executive retirement program liability	1,190	1,309
Total liabilities	$ 1,190	$ 1,309

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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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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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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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 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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