Quarterly Results of Operations (Unaudited) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
QuarterlyFinancialDataAbstract
Total revenues	$ 308,006	$ 250,028	$ 929,041	$ 824,127
Total benefits and expenses	197,204	(332,523)	656,470	(142,614)
Income Loss From Continuing Operations Before Income Taxes And Operating Joint Ventures	110,802	582,551	272,571	966,741
Net income	$ 96,037	$ 400,296	$ 230,966	$ 691,354