Loss And Loss Adjustment Expense Reserves (Schedule Of Insurance Loss Recoverable And Changes In Recoveries On Unpaid Losses) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Loss And Loss Adjustment Expense Recoveries [Line Items]
Gross Reserve beginning balance, Total	$ 3,980		$ 3,608
Collections for Cases with Recoveries	(3,011)		(13)
Accretion of Recoveries	25		39
Changes in Discount Rates	(71)		16
Changes in Assumptions	35		462
Changes in LAE Recoveries	(41)		13
Other	(17)	[1]	(145)	[1]
Gross Reserve ending balance, Total	900		3,980
Insurance Loss Recoverable [Member]
Loss And Loss Adjustment Expense Recoveries [Line Items]
Gross Reserve beginning balance, Insurance loss recoverable	3,648		3,046
Collections for Cases with Recoveries	(3,011)		(13)
Accretion of Recoveries	19		32
Changes in Discount Rates	(33)		4
Changes in Assumptions	126		700
Changes in LAE Recoveries	(38)		24
Other	(17)	[1]	(145)	[1]
Gross Reserve ending balance, Insurance loss recoverable	694		3,648
Recoveries On Unpaid Losses [Member]
Loss And Loss Adjustment Expense Recoveries [Line Items]
Gross Reserve beginning balance,Recoveries on unpaid losses	332		562
Collections for Cases with Recoveries	0		0
Accretion of Recoveries	6		7
Changes in Discount Rates	(38)		12
Changes in Assumptions	(91)		(238)
Changes in LAE Recoveries	(3)		(11)
Other	0	[1]	0	[1]
Gross Reserve ending balance, Recoveries on unpaid losses	$ 206		$ 332

[1] Primarily changes in amount and timing of collections.