Summary of Operating Results Related to Discontinued Operations (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenues:
Premiums		$ 927	$ 947	$ 1,858	$ 1,915
Net investment income		787	844	1,551	1,645
Net investment gains (losses)		8	70	36	103
Benefits and expenses:
Benefits and other changes in policy reserves		764	1,161	1,903	2,379
Acquisition and operating expenses, net of deferrals		589	304	860	579
Amortization of deferred acquisition costs and intangibles		84	86	176	163
Total benefits and expenses		1,588	1,721	3,241	3,473
Income from discontinued operations, net of taxes		(1)	(5)	(3)	16
Less: net income from discontinued operations attributable to noncontrolling interests		0	0	0	8
Income (loss) from discontinued operations available to Genworth Financial, Inc.'s common stockholders		$ (1)	(5)	$ (3)	8
Assets Held For Sale Related To Discontinued Operations | Genworth Australia
Revenues:
Premiums			0		51
Net investment income			0		4
Net investment gains (losses)			0		(5)
Total revenues			0		50
Benefits and expenses:
Benefits and other changes in policy reserves			0		11
Acquisition and operating expenses, net of deferrals			0		7
Amortization of deferred acquisition costs and intangibles			0		6
Interest expense			0		1
Total benefits and expenses			0		25
Income before income taxes and loss on sale	[1]		0		25
Provision for income taxes			0		8
Income before loss on sale			0		17
Loss on sale, net of taxes			0		(3)
Income from discontinued operations, net of taxes			0		14
Less: net income from discontinued operations attributable to noncontrolling interests			0		8
Income (loss) from discontinued operations available to Genworth Financial, Inc.'s common stockholders			$ 0		$ 6

[1] The six months ended June 30, 2021, includes pre-tax income from discontinued operations available to Genworth Financial, Inc.’s common stockholders of $13 million.