Dividends From Subsidiaries And Statutory Financial Information (Unaudited) (Schedule of Combined Net Income and Policyholders' Surplus in Accordance with Statutory Accounting Practices) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Insurance [Abstract]
Amount available for dividend distribution without prior approval from regulatory authorities	$ 417,000,000
Net income	417,441,000	574,181,000	407,449,000
Policyholders' surplus	$ 4,107,745,000	$ 4,154,654,000	$ 3,859,086,000