Reserves in Addition to Account Balance, Based on Expected No-Lapse Guarantee Benefits and Expected Policy Assessments (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	$ 2,454	$ 2,390
Ordinary/Traditional Life
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	848	815
Universal Life
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	511	508
Deferred Annuities
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	865	862
Structured Settlements
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	184	189
Other
Liability for Future Policy Benefit, by Product Segment [Line Items]
Life policy and investment contract reserves	$ 46	$ 16