Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Savings Plan
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan required years of service to vest for employees hired on or after January 1, 2011		2 years
Deposits recorded by our life insurance subsidiaries		$ 1	$ 1
Costs associated with plan		$ 12	11	$ 13
Maximum contribution to employees savings plans	5.00%			6.00%
Savings Plan | First 4% of pay deferred
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	100.00%
Maximum contribution to employees savings plans	4.00%
Savings Plan | Next 2% of pay deferred
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match	50.00%
Maximum contribution to employees savings plans	2.00%
Defined Contribution Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage funding of plan by Genworth		100.00%
Defined contribution pension plan required years of service to vest		3 years
Liability related to benefit plan		$ 11	11
Pension and Retiree Health and Life Insurance Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Costs associated with plan		22	21	$ 18
Retiree Health and Life Insurance Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Liability related to benefit plan		79	89
Change in other comprehensive income, (increase) reduction		$ (10)	(2)
Age for retirees receiving policy coverage		65 years
Number of years before retirement eligibility at which retiree medical benefits are available to employees		10 years
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Liability related to benefit plan		$ 71	77
Change in other comprehensive income, (increase) reduction		$ 6	$ 5