Schedule of Pre-Tax Gain (Loss) Recognized in Net Income (Loss) for Effects of Derivatives not Designated as Hedges (Detail) (Derivatives not designated as hedges, USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	$ (41)	$ 6	$ (64)	$ 5
Interest rate swaps | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	(3)	(3)	(8)	(8)
Interest rate swaps related to securitization entities | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	1	(1)	(5)	8
Credit default swaps | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	0	4	0	10
Credit default swaps related to securitization entities | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	(2)	24	16	49
Equity index options | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	(1)	(13)	(19)	(31)
Financial futures | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	22	(28)	66	(181)
Equity return swaps | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	6	(18)	1	(27)
Other foreign currency contracts | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	5	(2)	(6)	1
Foreign currency swaps | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	(4)	0	(3)	0
GMWB embedded derivatives | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	(58)	46	(87)	191
Fixed index annuity embedded derivatives | Net Investment Gains (Losses)
Derivative [Line Items]
Pre-tax gain (loss) recognized in net income (loss)	$ (7)	$ (3)	$ (19)	$ (7)