Condensed Consolidating Income Statement (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Premiums													$ 5,431	$ 5,148	$ 5,041
Net investment income													3,242	3,271	3,343
Net investment gains (losses)													(20)	(37)	27
Insurance and investment product fees and other													912	1,021	1,229
Total revenues	2,424		2,404		2,415		2,322		2,412	2,317	2,371	2,303	9,565	9,403	9,640
Benefits and expenses:
Benefits and other changes in policy reserves													6,620	4,895	5,378
Interest credited													737	738	775
Acquisition and operating expenses, net of deferrals													1,585	1,659	1,594
Amortization of deferred acquisition costs and intangibles													571	569	722
Goodwill impairment													849	0	89
Interest expense													479	492	476
Total benefits and expenses	3,347	[1]	3,376	[1]	2,102	[1]	2,016	[1]	2,097	2,066	2,124	2,066	10,841	8,353	9,034
Income (loss) from continuing operations before income taxes and equity in income (loss) of subsidiaries													(1,276)	1,050	606
Provision (benefit) for income taxes													(228)	324	138
Equity in income (loss) of subsidiaries													0	0	0
Income (loss) from continuing operations	(708)	[2]	(787)	[2]	228	[2]	219	[2]	245	146	174	161	(1,048)	726	468
Income (loss) from discontinued operations, net of taxes									0	2	6	(20)	0	(12)	57
Net income (loss)	(708)	[2]	(787)	[2]	228	[2]	219	[2]	245	148	180	141	(1,048)	714	525
Less: net income attributable to noncontrolling interests	52		57		52		35		37	40	39	38	196	154	200
Net income (loss) available to Genworth Financial, Inc.'s common stockholders	(760)	[2]	(844)	[2]	176	[2]	184	[2]	208	108	141	103	(1,244)	560	325
Parent Guarantor
Revenues:
Premiums													0	0	0
Net investment income													(2)	(1)	0
Net investment gains (losses)													0	0	0
Insurance and investment product fees and other													0	0	0
Total revenues													(2)	(1)	0
Benefits and expenses:
Benefits and other changes in policy reserves													0	0	0
Interest credited													0	0	0
Acquisition and operating expenses, net of deferrals													21	33	7
Amortization of deferred acquisition costs and intangibles													0	0	0
Goodwill impairment													0		0
Interest expense													0	0	0
Total benefits and expenses													21	33	7
Income (loss) from continuing operations before income taxes and equity in income (loss) of subsidiaries													(23)	(34)	(7)
Provision (benefit) for income taxes													(8)	13	(3)
Equity in income (loss) of subsidiaries													(1,229)	607	329
Income (loss) from continuing operations													(1,244)	560	325
Income (loss) from discontinued operations, net of taxes													0	0	0
Net income (loss)													(1,244)	560	325
Less: net income attributable to noncontrolling interests													0	0	0
Net income (loss) available to Genworth Financial, Inc.'s common stockholders													(1,244)	560	325
Issuer
Revenues:
Premiums													0	0	0
Net investment income													0	1	1
Net investment gains (losses)													4	6	(29)
Insurance and investment product fees and other													(4)	0	(1)
Total revenues													0	7	(29)
Benefits and expenses:
Benefits and other changes in policy reserves													0	0	0
Interest credited													0	0	0
Acquisition and operating expenses, net of deferrals													0	32	8
Amortization of deferred acquisition costs and intangibles													0	0	0
Goodwill impairment													0		0
Interest expense													321	322	315
Total benefits and expenses													321	354	323
Income (loss) from continuing operations before income taxes and equity in income (loss) of subsidiaries													(321)	(347)	(352)
Provision (benefit) for income taxes													(112)	(120)	(110)
Equity in income (loss) of subsidiaries													(1,147)	796	636
Income (loss) from continuing operations													(1,356)	569	394
Income (loss) from discontinued operations, net of taxes													0	(29)	0
Net income (loss)													(1,356)	540	394
Less: net income attributable to noncontrolling interests													0	0	0
Net income (loss) available to Genworth Financial, Inc.'s common stockholders													(1,356)	540	394
All Other Subsidiaries
Revenues:
Premiums													5,431	5,148	5,041
Net investment income													3,259	3,286	3,357
Net investment gains (losses)													(24)	(43)	56
Insurance and investment product fees and other													917	1,025	1,234
Total revenues													9,583	9,416	9,688
Benefits and expenses:
Benefits and other changes in policy reserves													6,620	4,895	5,378
Interest credited													737	738	775
Acquisition and operating expenses, net of deferrals													1,564	1,594	1,579
Amortization of deferred acquisition costs and intangibles													571	569	722
Goodwill impairment													849		89
Interest expense													174	189	179
Total benefits and expenses													10,515	7,985	8,722
Income (loss) from continuing operations before income taxes and equity in income (loss) of subsidiaries													(932)	1,431	966
Provision (benefit) for income taxes													(104)	431	251
Equity in income (loss) of subsidiaries													0	0	(38)
Income (loss) from continuing operations													(828)	1,000	677
Income (loss) from discontinued operations, net of taxes													0	17	57
Net income (loss)													(828)	1,017	734
Less: net income attributable to noncontrolling interests													196	154	200
Net income (loss) available to Genworth Financial, Inc.'s common stockholders													(1,024)	863	534
Eliminations
Revenues:
Premiums													0	0	0
Net investment income													(15)	(15)	(15)
Net investment gains (losses)													0	0	0
Insurance and investment product fees and other													(1)	(4)	(4)
Total revenues													(16)	(19)	(19)
Benefits and expenses:
Benefits and other changes in policy reserves													0	0	0
Interest credited													0	0	0
Acquisition and operating expenses, net of deferrals													0	0	0
Amortization of deferred acquisition costs and intangibles													0	0	0
Goodwill impairment													0		0
Interest expense													(16)	(19)	(18)
Total benefits and expenses													(16)	(19)	(18)
Income (loss) from continuing operations before income taxes and equity in income (loss) of subsidiaries													0	0	(1)
Provision (benefit) for income taxes													(4)	0	0
Equity in income (loss) of subsidiaries													2,376	(1,403)	(927)
Income (loss) from continuing operations													2,380	(1,403)	(928)
Income (loss) from discontinued operations, net of taxes													0	0	0
Net income (loss)													2,380	(1,403)	(928)
Less: net income attributable to noncontrolling interests													0	0	0
Net income (loss) available to Genworth Financial, Inc.'s common stockholders													$ 2,380	$ (1,403)	$ (928)

[1] During the fourth quarter of 2014, we completed our annual loss recognition testing of our long-term care insurance business which resulted in additional expenses of $735 million. During the fourth quarter of 2014, we also recorded goodwill impairments of $299 million in our U.S. Life Insurance segment. In the fourth quarter of 2014, we recorded a correction of $49 million in our life insurance business related to reserves on a reinsurance transaction. Our long-term care insurance claim reserves also increased in the fourth quarter of 2014 as a result of a $67 million unfavorable correction related to claims in course of settlement arising in connection with the implementation of our updated assumptions and methodologies as part of our comprehensive claims review completed in the third quarter of 2014, partially offset by a $43 million favorable refinement of assumptions for claim termination rates.

[2] During the fourth quarter of 2014, we completed our annual loss recognition testing of our long-term care insurance business which resulted in additional charges of $478 million, net of taxes. During the fourth quarter of 2014, we also recorded goodwill impairments of $274 million, net of taxes, in our U.S. Life Insurance segment. There was a $66 million net tax impact in the fourth quarter of 2014 from potential business portfolio changes. As we consider potential business portfolio changes, we recognized a charge of $174 million in the fourth quarter of 2014 associated with our Australian mortgage insurance business as we can no longer assert our intent to permanently reinvest earnings in that business. In addition, in the fourth quarter of 2014, we recognized a net $108 million of tax benefits in our lifestyle protection insurance business primarily from an internal debt restructuring related to the planned sale of that business. We recorded a correction of $32 million, net of taxes, in our life insurance business related to reserves on a reinsurance transaction in the fourth quarter of 2014. Our long-term care insurance claim reserves also increased in the fourth quarter of 2014 as a result of a $44 million unfavorable correction related to claims in course of settlement arising in connection with the implementation of our updated assumptions and methodologies as part of our comprehensive claims review completed in the third quarter of 2014, partially offset by a $28 million favorable refinement of assumptions for claim termination rates.