Description of shares vest as cash payment .

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- Definition

Number of trading days immediately preceding the vesting date.

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No definition available.

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- Definition

The weighted average fair value at grant date for a specific performance metric associated with nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

No definition available.

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- Definition

The weighted average fair value at grant date for a second performance metric associated with nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

No definition available.

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- Definition

Share Based Employee Compensation [Line Items]

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of tax benefit from exercise of option under share-based payment arrangement.

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- Definition

Amount of noncash expense for share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

Number of shares authorized for issuance under share-based payment arrangement.

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-Topic 718
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Long-Term Incentive Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2012
Share Based Employee Compensation [Line Items]
Long-term incentive compensation expense	$ 49	$ 37	$ 40
Stock-based compensation expense	$ 29	$ 19	21
Restricted Stock Units
Share Based Employee Compensation [Line Items]
Granted stock options, fair value	$ 6.05	$ 4.25
Cash Settled Restricted Stock Units
Share Based Employee Compensation [Line Items]
Granted stock options, fair value	$ 6.18	$ 4.27
Enact Holdings Inc.
Share Based Employee Compensation [Line Items]
Equity awards, total amount of shares authorized to be outstanding	4,000,000
Unrecognized stock-based compensation expense	$ 13	$ 13
Unrecognized stock-based compensation expense, expected weighted-average period of recognition (years)	2 years
Tax benefit realized from the exercise of share based awards	$ 1	1
Stock-based compensation expense	$ 15	$ 10	$ 2
Enact Holdings Inc. \| Performance Stock Units (PSUs)
Share Based Employee Compensation [Line Items]
Granted stock options, fair value	$ 24.23	$ 22.15
Average vesting period	3 years	3 years
Enact Holdings Inc. \| Restricted Stock Units
Share Based Employee Compensation [Line Items]
Granted stock options, fair value	$ 24.26	$ 22.18
Average vesting period	3 years	3 years	3 years
Genworth Financial Inc
Share Based Employee Compensation [Line Items]
Unrecognized stock-based compensation expense	$ 17	$ 16
Unrecognized stock-based compensation expense, expected weighted-average period of recognition (years)	2 years
Tax benefit realized from the exercise of share based awards	$ 4	$ 5
Genworth Financial Inc \| Performance Stock Units (PSUs)
Share Based Employee Compensation [Line Items]
Average vesting period	3 years	3 years	3 years
Stock-based compensation expense	$ 9	$ 3	$ 16
Performance metric grant-date fair value, metric two	$ 6.21	$ 4.27	$ 3.31
Performance metric grant-date fair value	$ 8.82	$ 5.3	$ 4.18
Genworth Financial Inc \| Restricted Stock Units
Share Based Employee Compensation [Line Items]
Average vesting period	3 years	3 years	3 years
Genworth Financial Inc \| Time Based Cash Settled Restricted Awards [Member]
Share Based Employee Compensation [Line Items]
Granted stock options, fair value		$ 1	$ 1
Average vesting period		3 years	3 years
Genworth Financial Inc \| Cash Settled Restricted Stock Units
Share Based Employee Compensation [Line Items]
Average vesting period	3 years	3 years
Description of shares vest as cash payment	one	one
Number of trading days immediately preceding the vesting date	20 days	20 days
Genworth Financial Inc \| Omnibus Incentive Plan
Share Based Employee Compensation [Line Items]
Equity awards, total amount of shares authorized to be outstanding				16,000,000
Equity awards, amount of shares authorized to grant			25,000,000
Long-term incentive compensation expense	$ 34	$ 27	$ 38
Genworth Financial Inc \| 2018 Omnibus Incentive Plan
Share Based Employee Compensation [Line Items]
Equity awards, total amount of shares authorized to be outstanding	25,000,000
Equity awards, amount of shares authorized to grant	20,000,000
Genworth Financial Inc \| 2021 Omnibus Incentive Plan
Share Based Employee Compensation [Line Items]
Equity awards, total amount of shares authorized to be outstanding	25,000,000
Equity awards, amount of shares authorized to grant	20,000,000