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Additional maximum borrowing capacity whereby the commitments under the credit facility may be increased on an uncommitted basis.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Face (par) amount of the original debt instrument that was repurchased.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Maturity date of long-term debt, in YYYY-MM-DD format.

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Borrowings and Other Financings - Additional Information (Detail) - USD ($) $ in Millions		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2024	May 28, 2024
Genworth Holdings \| Floating Rate Junior Subordinated Notes, due 2066
Debt Instrument [Line Items]
Aggregate principal amount of notes repurchased		$ 18
Debt instrument, maturity year		2066
Pre-tax gain (loss) on early extinguishment of debt		$ 3
Enact Holdings \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt Instrument, Term	5 years
Line of credit facility, maximum borrowing capacity	$ 200
Line of credit facility, additional borrowing capacity	$ 100
Enact Holdings \| 6.25% Senior Notes, due 2029
Debt Instrument [Line Items]
Debt instrument face amount			$ 750
Long-term debt maturity date		May 28, 2029
Interest rate		6.25%
Long term debt terms of interest payment		payable semi-annually in arrears on May 28 and November 28 of each year
Debt instrument, maturity year		2029
Debt instrument featured call date		Apr. 28, 2029
Debt instrument basis spread		0.30%
Debt instrument, redemption price, percentage		100.00%
Enact Holdings \| 6.50% Senior Notes, due 2025
Debt Instrument [Line Items]
Interest rate		6.50%
Debt instrument, maturity year		2025
Pre-tax gain (loss) on early extinguishment of debt		$ (11)