Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Comprehensive income (loss), net of tax
Net income (loss)	$ 442,099us-gaap_ProfitLoss	$ 265,623us-gaap_ProfitLoss	$ 41,247us-gaap_ProfitLoss
Other comprehensive income (loss)
Net unrealized gain (loss) on securities	89,415	35,352	15,526
Reclassification of net realized (gain) loss on securities into earnings	(64,310)	(47,664)	0
Total other comprehensive income (loss)	25,105	(12,312)	15,526
Total comprehensive income (loss)	467,204us-gaap_ComprehensiveIncomeNetOfTax	253,311us-gaap_ComprehensiveIncomeNetOfTax	56,773us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive income (loss) attributable to noncontrolling interests	89,222	(326)	0
Comprehensive income (loss) attributable to common stockholders	$ 377,982	$ 253,637	$ 56,773

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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