Summary of Net Operating Income (Loss) for Segments and Corporate and Other Activities (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Net operating income (loss)	$ 133	$ 67	$ 284	$ 84
Net investment gains (losses), net of taxes and other adjustments	15	(18)	(13)	(1)
Income (loss) from discontinued operations, net of taxes	6	27	(14)	39
Expenses related to restructuring, net of taxes	(13)	0	(13)	0
Net income available to Genworth Financial, Inc.'s common stockholders	141	76	244	122
Add: net income attributable to noncontrolling interests	39	33	77	66
Net income	180	109	321	188
Life Insurance
Segment Reporting Information [Line Items]
Net operating income (loss)	27	30	63	36
Long-term Care Insurance
Segment Reporting Information [Line Items]
Net operating income (loss)	26	14	46	49
Fixed Annuities
Segment Reporting Information [Line Items]
Net operating income (loss)	26	20	55	43
U.S. Life Insurance
Segment Reporting Information [Line Items]
Net operating income (loss)	79	64	164	128
Canada Mortgage Insurance
Segment Reporting Information [Line Items]
Net operating income (loss)	43	41	85	78
Australia Mortgage Insurance
Segment Reporting Information [Line Items]
Net operating income (loss)	55	44	101	23
Other Countries
Segment Reporting Information [Line Items]
Net operating income (loss)	(9)	(9)	(16)	(18)
International Mortgage Insurance
Segment Reporting Information [Line Items]
Net operating income (loss)	89	76	170	83
U.S. Mortgage Insurance
Segment Reporting Information [Line Items]
Net operating income (loss)	13	(25)	34	(69)
International Protection
Segment Reporting Information [Line Items]
Net operating income (loss)	1	3	7	8
Runoff
Segment Reporting Information [Line Items]
Net operating income (loss)	6	(6)	22	29
Corporate and Other
Segment Reporting Information [Line Items]
Net operating income (loss)	$ (55)	$ (45)	$ (113)	$ (95)