Realized and Unrealized Investment Gains (Losses) (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	$ 147,998,000	$ 176,588,000	$ 557,444,000
Income tax expense	(52,381,000)	(61,227,000)	(195,813,000)
Noncontrolling interests	55,000	(8,000)	(21,000)
Total change in unrealized gains and losses	95,672,000	115,353,000	361,610,000
Change in valuation allowance for loans receivable	0	6,082,000	12,418,000
Fixed Maturities Securites [Member]
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	209,467,000	102,488,000	405,950,000
Less Non-Credit Portion of OTTI Recognized In Other Comprehensive Income [Member]
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	(3,604,000)	1,362,000	(5,425,000)
Equity Securities Available For Sale [Member]
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	(55,772,000)	68,178,000	143,684,000
Investment funds [Member]
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	$ (2,093,000)	$ 4,560,000	$ 13,235,000