Summary of Operating Results Related to Discontinued Operations (Parenthetical) (Detail) $ in Millions	6 Months Ended
Jun. 30, 2021 USD ($)
Genworth Australia \| Parent Company [Member]
Discontinued operation pretax income attributable to parent	$ 13

Amount before tax of income (loss) from operations classified as a discontinued operation attributable to the parent. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

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