CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
Net income (loss)	$ 131,762us-gaap_NetIncomeLoss	$ 43,313us-gaap_NetIncomeLoss	$ (29,781)us-gaap_NetIncomeLoss
Unrealized gains (losses) on available-for-sale securities:
Unrealized (losses) gains during period, net of income taxes	(30)	(37)	58
Less: Reclassification adjustments for gains included to net income (loss), net of taxes		1	14
Net unrealized (losses) gains on available-for-sale securities	(30)	(38)	44
Comprehensive income (loss)	$ 131,732us-gaap_ComprehensiveIncomeNetOfTax	$ 43,275us-gaap_ComprehensiveIncomeNetOfTax	$ (29,737)us-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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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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

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