Reinsurance (Summary Of The Impact On Life In Force) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reinsurance [Abstract]
Direct	$ 6,528	$ 8,015	$ 9,159
Assumed
Ceded	6,515	8,001	9,144
Net	$ 13	$ 14	$ 15