Quarterly Results of Operations (Unaudited) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
QuarterlyFinancialDataAbstract
Total revenues	$ 283,524	$ 375,418	$ 574,100	$ 688,619
Total benefits and expenses	96,720	716,619	189,910	498,621
Income Loss From Continuing Operations Before Income Taxes And Operating Joint Ventures	186,804	(341,201)	384,190	189,998
Net income	$ 143,670	$ (237,147)	$ 291,058	$ 135,200

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

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