Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Comprehensive income (loss), net of tax
Net income	$ 41,798us-gaap_ProfitLoss	$ 56,865us-gaap_ProfitLoss
Other comprehensive income (loss)
Net unrealized gain on securities	15,132	10,878
Reclassification of net realized (gain) on securities into earnings	(23,626)	(4,164)
Total other comprehensive income (loss)	(8,494)	6,714
Total comprehensive income	33,304us-gaap_ComprehensiveIncomeNetOfTax	63,579us-gaap_ComprehensiveIncomeNetOfTax
Comprehensive income attributable to noncontrolling interests	5,823	8,093
Comprehensive income attributable to common stockholders	$ 27,481	$ 55,486

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 other comprehensive income (loss).

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