Schedule of Deferred Acquisition Cost and Future Policy Benefits Payable With Our Long-Duration Insurance Products (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Deferred Policy Acquisition Costs And Insurance Expenses [Line Items]
Other long-term assets, Deferred acquisition Costs	$ 149	$ 114
Trade accounts payable and accrued expenses, Deferred acquisition Cost	0	0
Long-term liabilities, Deferred acquisition Cost	0	0
Total asset (liability), Deferred acquisition Cost	149	114
Other long-term assets, Future policy benefits payable	0	0
Trade accounts payable and accrued expenses, Future policy benefits payable	(63)	(58)
Long-term liabilities, Future policy benefits payable	(1,858)	(1,663)
Total asset (liability), Future policy benefits payable	$ (1,921)	$ (1,721)