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	3 Months Ended
	Mar. 31, 2014
Loss And Loss Adjustment Expense Recoveries [Line Items]
Gross Reserve beginning balance, Total	$ 900
Collections for Cases with Recoveries	(17)
Accretion of Recoveries	5
Changes in Discount Rates	13
Changes in Assumptions	(39)
Changes in LAE Recoveries	0
Other	(9)	[1]
Gross Reserve ending balance, Total	853
Insurance Loss Recoverable [Member]
Loss And Loss Adjustment Expense Recoveries [Line Items]
Gross Reserve beginning balance, Insurance loss recoverable	694
Collections for Cases with Recoveries	(17)
Accretion of Recoveries	4
Changes in Discount Rates	6
Changes in Assumptions	(7)
Changes in LAE Recoveries	0
Other	(9)	[1]
Gross Reserve ending balance, Insurance loss recoverable	671
Recoveries On Unpaid Losses [Member]
Loss And Loss Adjustment Expense Recoveries [Line Items]
Gross Reserve beginning balance,Recoveries on unpaid losses	206
Collections for Cases with Recoveries	0
Accretion of Recoveries	1
Changes in Discount Rates	7
Changes in Assumptions	(32)
Changes in LAE Recoveries	0
Other	0	[1]
Gross Reserve ending balance, Recoveries on unpaid losses	$ 182

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