CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
General and administrative expense	$ 4,880us-gaap_GeneralAndAdministrativeExpense	$ 5,239us-gaap_GeneralAndAdministrativeExpense
Operating loss	(4,880)us-gaap_OperatingIncomeLoss	(5,239)us-gaap_OperatingIncomeLoss
Other income (loss), net	(388)us-gaap_OtherNonoperatingIncomeExpense	30,374us-gaap_OtherNonoperatingIncomeExpense
Interest income	449us-gaap_InvestmentIncomeInterest	470us-gaap_InvestmentIncomeInterest
Interest expense	(1,122)us-gaap_InterestExpenseDebt	(1,094)us-gaap_InterestExpenseDebt
Equity income (loss)	(8,662)	6,808
Net income (loss) before income taxes	(14,603)	31,319
Income tax benefit (expense)	0us-gaap_IncomeTaxExpenseBenefit	0us-gaap_IncomeTaxExpenseBenefit
Net loss	$ (14,603)us-gaap_ProfitLoss	$ 31,319us-gaap_ProfitLoss
Net income (loss) per share:
Basic (in dollars per share)	$ (0.70)us-gaap_EarningsPerShareBasic	$ 1.44us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ (0.70)us-gaap_EarningsPerShareDiluted	$ 1.29us-gaap_EarningsPerShareDiluted
Weighted average shares used in computing income (loss) per share :
Basic (in shares)	20,861	21,687
Diluted (in shares)	20,861	25,121

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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