Condensed Consolidating Statement of Comprehensive Income (Detail) - USD ($) $ in Millions		3 Months Ended																12 Months Ended
		Dec. 31, 2016	[1]	Sep. 30, 2016	[1]	Jun. 30, 2016	[1]	Mar. 31, 2016	[1]	Dec. 31, 2015	[2],[3]	Sep. 30, 2015	[2],[3]	Jun. 30, 2015	[2],[3]	Mar. 31, 2015	[2],[3]	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Net income (loss)		$ (63)		$ (332)		$ 220		$ 108		$ (240)		$ (238)		$ (139)		$ 204		$ (67)	$ (413)	$ (1,048)
Other comprehensive income (loss), net of taxes:
Net unrealized gains (losses) on securities not other-than-temporarily impaired																		6	(1,209)	1,573
Net unrealized gains (losses) on other-than- temporarily impaired securities																		(9)	(4)	10
Derivatives qualifying as hedges	[4]																	40	(25)	751
Foreign currency translation and other adjustments																		54	(530)	(537)
Total other comprehensive income (loss)																		91	(1,768)	1,797
Total comprehensive income (loss)																		24	(2,181)	749
Less: comprehensive income (loss) attributable to noncontrolling interests																		217	(106)	32
Total comprehensive income (loss) available to Genworth Financial, Inc.'s common stockholders																		(193)	(2,075)	717
Parent Guarantor
Condensed Financial Statements, Captions [Line Items]
Net income (loss)																		(277)	(615)	(1,244)
Other comprehensive income (loss), net of taxes:
Net unrealized gains (losses) on securities not other-than-temporarily impaired																		17	(1,181)	1,539
Net unrealized gains (losses) on other-than- temporarily impaired securities																		(9)	(4)	10
Derivatives qualifying as hedges																		40	(25)	751
Foreign currency translation and other adjustments																		36	(250)	(339)
Total other comprehensive income (loss)																		84	(1,460)	1,961
Total comprehensive income (loss)																		(193)	(2,075)	717
Less: comprehensive income (loss) attributable to noncontrolling interests																		0	0	0
Total comprehensive income (loss) available to Genworth Financial, Inc.'s common stockholders																		(193)	(2,075)	717
Issuer
Condensed Financial Statements, Captions [Line Items]
Net income (loss)																		(459)	(657)	(1,356)
Other comprehensive income (loss), net of taxes:
Net unrealized gains (losses) on securities not other-than-temporarily impaired																		14	(1,158)	1,510
Net unrealized gains (losses) on other-than- temporarily impaired securities																		(6)	(4)	11
Derivatives qualifying as hedges																		39	(24)	751
Foreign currency translation and other adjustments																		(28)	(171)	(273)
Total other comprehensive income (loss)																		19	(1,357)	1,999
Total comprehensive income (loss)																		(440)	(2,014)	643
Less: comprehensive income (loss) attributable to noncontrolling interests																		0	0	0
Total comprehensive income (loss) available to Genworth Financial, Inc.'s common stockholders																		(440)	(2,014)	643
All Other Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net income (loss)																		450	(183)	(828)
Other comprehensive income (loss), net of taxes:
Net unrealized gains (losses) on securities not other-than-temporarily impaired																		7	(1,210)	1,573
Net unrealized gains (losses) on other-than- temporarily impaired securities																		(9)	(4)	10
Derivatives qualifying as hedges																		43	(19)	794
Foreign currency translation and other adjustments																		54	(530)	(537)
Total other comprehensive income (loss)																		95	(1,763)	1,840
Total comprehensive income (loss)																		545	(1,946)	1,012
Less: comprehensive income (loss) attributable to noncontrolling interests																		217	(106)	32
Total comprehensive income (loss) available to Genworth Financial, Inc.'s common stockholders																		328	(1,840)	980
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net income (loss)																		219	1,042	2,380
Other comprehensive income (loss), net of taxes:
Net unrealized gains (losses) on securities not other-than-temporarily impaired																		(32)	2,340	(3,049)
Net unrealized gains (losses) on other-than- temporarily impaired securities																		15	8	(21)
Derivatives qualifying as hedges																		(82)	43	(1,545)
Foreign currency translation and other adjustments																		(8)	421	612
Total other comprehensive income (loss)																		(107)	2,812	(4,003)
Total comprehensive income (loss)																		112	3,854	(1,623)
Less: comprehensive income (loss) attributable to noncontrolling interests																		0	0	0
Total comprehensive income (loss) available to Genworth Financial, Inc.'s common stockholders																		$ 112	$ 3,854	$ (1,623)

[1] We completed our annual review of assumptions in the fourth quarter of 2016 as described above, which resulted in $196 million, net of taxes, of charges in our universal and term universal life insurance products.

[2] We completed our annual review of assumptions in the fourth quarter of 2015, which primarily resulted in $194 million, net of taxes, of charges, which included $36 million, net of taxes, of corrections related to reinsurance inputs, in our universal and term universal life insurance products. We also recorded an expected loss of $134 million, net of taxes, related to the planned sale of our mortgage insurance business in Europe in the fourth quarter of 2015.

[3] We completed the sale of our lifestyle protection insurance business on December 1, 2015 and recorded an additional loss of $63 million, net of taxes, in the fourth quarter of 2015. The additional loss in the fourth quarter of 2015 was primarily related to the write off of currency translation adjustments on a holding company that was not part of the sale but related to our lifestyle protection insurance business that was substantially liquidated after the completion of the sale.

[4] See note 5 for additional information.