Summary of Operating Results Related to Discontinued Operations (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Parent Company [Member]
Discontinued operation pretax income attributable to parent			$ 186
Genworth Canada Mortgage Insurance
Interest expense-term loan			34
Genworth Australia \| Parent Company [Member]
Discontinued operation pretax income attributable to parent	$ 13	$ 54	$ 100

Amount of interest expense attributable to disposal group, including, but not limited to, discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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