Fair Value Measurements (Details) (USD $)	3 Months Ended
Mar. 31, 2013
Fair Value Measurements [Abstract]
Fair value and carrying value of debt	$ 19,700,000
Fair Value Measurements [Abstract]
Available for sale securities	144,000
Assets held for sale	15,369,000
Total assets	15,513,000
Commodity risk management liability	145,000
Other accrued liabilities	742,000
Total	887,000
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning of period	17,051,000
Sale of Assets	(1,884,000)
Revision of value	202,000
End of period	15,369,000
Asset Held For Sale [Member] \| Remington Village [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning of period	15,167,000
Sale of Assets	0
Revision of value	202,000
End of period	15,369,000
Asset Held For Sale [Member] \| Corporate Aircraft and Facilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning of period	1,884,000
Sale of Assets	(1,884,000)
Revision of value	0
End of period	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Measurements [Abstract]
Available for sale securities	144,000
Assets held for sale	0
Total assets	144,000
Commodity risk management liability	0
Other accrued liabilities	0
Total	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Measurements [Abstract]
Available for sale securities	0
Assets held for sale	0
Total assets	0
Commodity risk management liability	145,000
Other accrued liabilities	0
Total	145,000
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Measurements [Abstract]
Available for sale securities	0
Assets held for sale	15,369,000
Total assets	15,369,000
Commodity risk management liability	0
Other accrued liabilities	742,000
Total	$ 742,000

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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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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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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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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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Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of 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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This element represents the aggregate of the liabilities 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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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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