Fair Value Measurements (Details) (USD $)	6 Months Ended
Jun. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other accrued liabilities	$ 795,000
Fair Value Measurements [Abstract]
Commodity risk management assets	1,112,000
Available for sale securities	221,000
Assets held for sale	16,180,000
Total assets	17,513,000
Fair value and carrying value of debt	15,200,000
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
December 31, 2011	18,132,000
Revision of value	(1,952,000)
June 30, 2012	16,180,000
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements [Abstract]
Commodity risk management assets	0
Available for sale securities	221,000
Assets held for sale	0
Total assets	221,000
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements [Abstract]
Commodity risk management assets	1,112,000
Available for sale securities	0
Assets held for sale	0
Total assets	1,112,000
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements [Abstract]
Commodity risk management assets	0
Available for sale securities	0
Assets held for sale	16,180,000
Total assets	$ 16,180,000

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-Number 210

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This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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- Definition

Long-lived assets that are held for sale apart from normal operations and anticipated to be sold in less than one year.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 33

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Name Accounting Standards Codification

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Amount of increase (decrease) of assets measured at fair value on a recurring basis using unobservable inputs (level 3). Such increase (decrease) may be comprised of changes in fair value (gains or losses) whether realized or unrealized that have been included in earnings, changed net asset value, or other comprehensive income (a separate component of shareholders' equity); purchases, sales, issues, or settlements of assets; and net transfers in to or out of this category within the fair value hierarchy.

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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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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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