Assumed Life Reinsurance Programs Involving Minimum Benefit Guarantees Under Annuity Contracts (Schedule Of Guaranteed Minimum Benefits Income And Expense) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Guaranteed Minimum Benefits [Line Items]
Net premiums earned	$ 3,970	$ 3,573
Policy benefits and other reserve adjustments	114	131
Net realized gains (losses)	(104)	206
Guaranteed Minimum Death Benefit [Member]
Guaranteed Minimum Benefits [Line Items]
Net premiums earned	19	20
Policy benefits and other reserve adjustments	15	19
Guaranteed Minimum Income Benefit [Member]
Guaranteed Minimum Benefits [Line Items]
Net premiums earned	36	39
Policy benefits and other reserve adjustments	9	9
Net realized gains (losses)	(50)	369
Gain (loss) recognized in income	(23)	399
Net cash received	33	32
Net (increase) decrease in liability	$ (56)	$ 367