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		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Guaranteed Minimum Benefits [Line Items]
Net premiums earned	$ 4,332	$ 4,067	$ 8,302	$ 7,640
Policy benefits and other reserve adjustments	144	110	258	241
Net realized gains (losses)	(73)	104	(177)	310
Guaranteed Minimum Death Benefit [Member]
Guaranteed Minimum Benefits [Line Items]
Net premiums earned	18	20	37	40
Policy benefits and other reserve adjustments	13	25	28	44
Guaranteed Minimum Income Benefit [Member]
Guaranteed Minimum Benefits [Line Items]
Net premiums earned	34	37	70	76
Policy benefits and other reserve adjustments	10	2	19	11
Net realized gains (losses)	2	101	(48)	470
Gain recognized in income	26	136	3	535
Net cash received	29	31	62	63
Net (increase) decrease in liability	$ (3)	$ 105	$ (59)	$ 472