Sale of Businesses - Additional Information (Detail) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2019 USD ($) $ / shares
Life Insurance Protection
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Litigation expense	$ 110
Discontinued Operations, Disposed of by Sale \| Life Insurance Protection
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Gain (loss) on sale of discontinued operations, net of taxes		$ 9
Litigation expense	110	110
Genworth Canada MI
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Net cash proceeds from sale of business		$ 1,700
Payments of dividends to holding company	$ 54
Special dividend reducing the purchase price per share \| $ / shares	$ 1.45	$ 1.45
Gain (loss) on sale of discontinued operations, net of taxes	$ 43	$ (121)

Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]

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- Definition

Cash paid in the form of dividends to the holding company.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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- Definition

The cash inflow associated with the amount received from the sale of a business segment or subsidiary or sale of an entity that is related to it but not strictly controlled during the period (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

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