CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (14,603)us-gaap_ProfitLoss	$ 31,319us-gaap_ProfitLoss
Other comprehensive income (loss), before taxes:
Unrealized net loss on available-for-sale securities	0	(3)
Reclassification adjustment for other than temporary impairment of available-for-sale securities included in net income (loss)	0	3
Total comprehensive income (loss)	$ (14,603)us-gaap_ComprehensiveIncomeNetOfTax	$ 31,319us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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-Name Accounting Standards Codification

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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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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