Favorable adjustment relating to the company's tax matters agreement.

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

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- Definition

Amounts associated with settling a legal claim on a business previously sold and accounted for as discontinued operations.

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- Definition

The amount owed associated with a tax gross up on underwriting losses reported as discontinued operations.

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- Definition

Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of increase (decrease) in loss contingency liability.

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Amount of cash outflow reducing loss contingency liability.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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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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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

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No definition available.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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No definition available.

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Discontinued Operations - Additional Information (Detail) $ / shares in Units, £ in Millions, shares in Millions, $ in Millions, $ in Millions							1 Months Ended	3 Months Ended		6 Months Ended
	Sep. 21, 2021 USD ($)	Sep. 21, 2021 GBP (£)	Mar. 31, 2021 USD ($)	Mar. 31, 2021 GBP (£)	Mar. 03, 2021 AUD ($) $ / shares shares	Mar. 03, 2021 USD ($) shares	Feb. 28, 2022 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 GBP (£)
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Unrelated liability								$ 3		$ 3		$ 4
Underwriting Liability [Member] \| AXA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Adjustments to underwriting loss											$ 4
Genworth Mortgage Insurance Australia Limited
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Proceeds from sale of disposal group including discontinuing operations					$ 483	$ 370
After-tax favorable adjustment										(1)	11
Percentage of shareholding in the investee company					52.00%	52.00%
Sale price per share disposed \| $ / shares					$ 2.28
Number of subsidiaries shares sold \| shares					214.3	214.3
AXA Settlement Agreement
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Income (losses) from discontinued operations after tax								$ 1	$ 4	$ 2	$ 5
AXA Settlement Agreement Promissory Note \| Discontinued Operations \| Future Claims
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Reduction in liabilities associated with future claims							$ 30
Loss Contingency, Estimate of Possible Loss												$ 30	£ 22
AXA Settlement Agreement Promissory Note \| Discontinued Operations \| Promissory Note \| Mandatory Payment
Income Statement, Balance Sheet and Additional Disclosures by Planned Disposal Groups [Line Items]
Repayment of mandatory principal payment	$ 296	£ 215	$ 245	£ 176