Investment in Savoy (Condensed Balance Sheet - Savoy) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets	$ 86,524us-gaap_AssetsCurrent	$ 84,409us-gaap_AssetsCurrent
Total assets	576,536us-gaap_Assets	579,585us-gaap_Assets
Total liabilities	379,530us-gaap_Liabilities	389,710us-gaap_Liabilities
Total liabilities and stockholders' equity	576,536	579,585
Savoy [Member]
Current assets	11,698
Oil and gas properties, net	27,578
Total assets	39,276
Total liabilities	5,538
Partners' capital	33,738
Total liabilities and stockholders' equity	$ 39,276

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Oil and gas properties net of accumulated depreciation, depletion, amortization, impairment, and abandonment, carried under the successful effort method.

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The amount of ownership interest of different classes of partners in limited partnership.

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