Intangible Assets (Value Of Business Acquired (VOBA) Roll-forward) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Movement in Intangible Assets Arising from Insurance Contracts Acquired in Business Combination [Roll Forward]
Balance, beginning of year	$ 536	$ 614	$ 676
Amortization expense	(51)	(64)	(82)
Foreign exchange revaluation	(19)	(14)	20
Balance, end of year	$ 466	$ 536	$ 614