Investments (Credit Losses Recognized In Earnings Related To OTTI Losses Recognized In Accumulated Other Comprehensive Income (Loss)) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Other than temporary impairment credit lossesfor available for sale securities rollforward [Abstract]
Beginning Balance	$ 175		$ 197		$ 341
Additions For Credit Loss Impairments Recognized In The Current Period On Securities Not Previous Impaired	15		0		0
Additions For Credit Loss Impairments Recognized In The Current Period On Securities Previously Impaired	1		0		8
Additions For Credit Loss Impairments Recognized in Prior Periods For Securities That Were Reimpaired With Non Credit Component In Current Period	0		0		0
Reductions For Credit Loss Impairments Previously Recognized On Securities Sold During The Period	(174)		(16)		(41)
Reductions For Credit Loss Impairments Previously Recognized On Securities Impaired To Fair Value During The Period	0	[1]	0	[1]	(111)	[1]
Reductions For Increases In Cash Flows Expected To Be Collected Over The Remaining Life Of The Security	(1)		(6)		0
Ending Balance	$ 16		$ 175		$ 197

[1] Represents circumstances where the Company determined in the current period that it intends to sell the security or it is more likely than not that it will be required to sell the security before recovery of the security's amortized cost.