Amount of subsidiary common shares distributed as a deemed capital contribution (non-cash).

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The amount of cash received as capital contribution from the parent company.

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Amount to reconcile the differences as of the balance sheet date resulting from applying permitted statutory accounting practices rather than statutory accounting practices permitted by local regulatory requirements of our international insurance subsidiaries.

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Limited guarantee provided to a subsidiary that is accounted for as a derivative and carried at fair value.

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Maximum risk-to-capital ratio enforced by the North Carolina Department Of Insurance.

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Statutory contingency reserve for U.S. mortgage insurance subsidiaries must be held until the earlier of 10 years or the time that the loss ratio exceeds 35%.

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Number of years from publication date of private mortgage insurance eligibility requirements guidelines to comply with defined capital levels.

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The risk based capital ratio is defined by the National Association of Insurance Commissioners and applies to our life insurance companies on a consolidated basis. The ratio is based upon four categories of risk: asset risk, insurance risk, interest rate and market risk, and business risk. The capital requirement for each is generally determined by applying factors which vary based upon the degree of risk to various asset, premium and reserve items.

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The risk to capital ratio as defined by certain states and other regulators to impose a form of capital requirements on our domestic mortgage insurance companies requiring maintenance of a risk to capital ratio not to exceed 25:1.

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Statutory contingency reserve required to be held by U.S. mortgage insurance subsidiaries, as defined by state law.

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Annual additions to the statutory contingency reserve for U.S. mortgage insurance subsidiaries must be equal to the greater of 50% of earned premiums or required level of policyholders position, as defined by state law.

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Amount by which surplus levels exceeded local supervisory solvency requirements.

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Amount of restricted net assets of consolidated and unconsolidated subsidiaries as of the end of the most recently completed fiscal year.

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This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

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Ratio of insurance contracts that are subject to reinsurance participation to all contracts in force.

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Face (par) amount of debt instrument at time of issuance.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Amount of an item which resulted in a difference from applying state prescribed or permitted statutory accounting practices rather than statutory accounting practices prescribed by National Association of Insurance Commissioners.

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Amount of each item listed to reconcile the differences as of the balance sheet date resulting from applying state permitted statutory accounting practices rather than statutory accounting practices permitted by National Association of Insurance Commissioners.

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

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Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

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Insurance Subsidiary Financial Information and Regulatory Matters - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	May 31, 2014	Dec. 31, 2013	Apr. 02, 2013	Jan. 31, 2013
Statutory Accounting Practices [Line Items]
Amount of dividend our subsidiaries could pay in 2015 without obtaining regulatory approval	$ 500,000,000
Dividends received from insurance subsidiaries	0	0	0
Additional statutory reserves	70,000,000	80,000,000			80,000,000
Statutory contingency reserve, annual additions, percentage of earned premiums, minimum	50.00%
Minimum loss ratio requirement to hold statutory contingency reserve	35.00%
Period of time when statutory contingency reserve has to be held, in years	10 years
Statutory contingency reserve	193,000,000gnw_StatutoryContingencyReserve	59,000,000gnw_StatutoryContingencyReserve			59,000,000gnw_StatutoryContingencyReserve
Genworth Financial's Subsidiaries
Statutory Accounting Practices [Line Items]
Restricted net assets	14,400,000,000
Genworth Holdings' Subsidiaries
Statutory Accounting Practices [Line Items]
Restricted net assets	14,500,000,000
Genworth Mortgage Insurance Corporation (GEMICO)
Statutory Accounting Practices [Line Items]
Capital contribution				300,000,000	100,000,000	100,000,000
Genworth Mortgage Holdings, LLC
Statutory Accounting Practices [Line Items]
Capital contribution					300,000,000
Genworth Holdings
Statutory Accounting Practices [Line Items]
Issued notes, aggregate principal amount		400,000,000			400,000,000
Rivermont Insurance Company I
Statutory Accounting Practices [Line Items]
Maximum potential amount of future obligation	95,000,000
Limited Guarantee Provided to a subsidiary accounted for as a derivative	5,000,000	0			0
U.S. Mortgage Insurance subsidiaries
Statutory Accounting Practices [Line Items]
Maximum risk-to-capital ratio	25
Number of states with risk-to-capital requirements	15
Private mortgage insurance eligibility requirements guidelines, transition period, years	2 years
Amount of subsidiary common shares distributed as a capital contribution							230,000,000
U.S. Mortgage Insurance subsidiaries \| Genworth Mortgage Insurance Corporation (GEMICO)
Statutory Accounting Practices [Line Items]
Risk-to-capital ratio	14.3	19.3			19.3
Long-term Care Insurance \| Brookfield Life and Annuity Insurance Company Limited ("BLAIC")
Statutory Accounting Practices [Line Items]
Percent of in-force long-term care insurance business, reinsured	50.00%
Australian Mortgage Insurance Subsidiaries \| Brookfield Life and Annuity Insurance Company Limited ("BLAIC")
Statutory Accounting Practices [Line Items]
Ownership percentage	66.20%
Canadian Mortgage Insurance Subsidiaries \| Brookfield Life and Annuity Insurance Company Limited ("BLAIC")
Statutory Accounting Practices [Line Items]
Ownership percentage	40.60%
Lifestyle Protection Insurance \| Brookfield Life and Annuity Insurance Company Limited ("BLAIC")
Statutory Accounting Practices [Line Items]
Ownership percentage	100.00%
Domestic insurance subsidiaries
Statutory Accounting Practices [Line Items]
Dividends received from insurance subsidiaries	108,000,000	418,000,000	374,000,000
Domestic insurance subsidiaries \| Extraordinary Dividend
Statutory Accounting Practices [Line Items]
Dividends received from insurance subsidiaries	0	0	175,000,000
International insurance subsidiaries
Statutory Accounting Practices [Line Items]
Dividends received from insurance subsidiaries	630,000,000	317,000,000	240,000,000
Combined statutory capital and surplus	6,968,000,000	8,248,000,000			8,248,000,000
Capital contribution							21,000,000
Combined statutory net income (loss)	(65,000,000)	605,000,000	1,190,000,000
Statutory capital and surplus required	2,506,000,000	3,435,000,000			3,435,000,000
Increase (decrease) in statutory capital	205,000,000	359,000,000
U.S. domiciled life insurance subsidiaries
Statutory Accounting Practices [Line Items]
Impact of permitted practices on combined statutory capital and surplus	365,000,000	450,000,000
Consolidated RBC ratio	435.00%	485.00%			485.00%
Domestic subsidiaries
Statutory Accounting Practices [Line Items]
Combined statutory capital and surplus	4,352,000,000	4,003,000,000			4,003,000,000
Combined statutory net income (loss)	(262,000,000)	342,000,000	(237,000,000)
Domestic subsidiaries \| Captive life reinsurance subsidiaries
Statutory Accounting Practices [Line Items]
Combined statutory capital and surplus	1,057,000,000	1,101,000,000			1,101,000,000
Combined statutory net income (loss)	(281,000,000)	(102,000,000)	(478,000,000)
Insurance Subsidiary \| NEW YORK
Statutory Accounting Practices [Line Items]
Additional statutory reserves	39,000,000
Insurance Subsidiary \| NEW YORK \| To be recoreded over the next four years
Statutory Accounting Practices [Line Items]
Additional statutory reserves	156,000,000
Guarantees provided to third parties
Statutory Accounting Practices [Line Items]
Maximum potential amount of future obligation	$ 28,000,000	$ 30,000,000			$ 30,000,000