Borrowings and Other Financings - Long Term Borrowings (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Deferred borrowing charges	$ (15)	$ (15)
Total	4,570	4,612
Genworth Holdings
Debt Instrument [Line Items]
Long-term borrowings	4,100	4,151
Deferred borrowing charges	(21)	(24)
Total	4,079	4,127
Genworth Holdings \| 8.625% Senior Notes, Due 2016
Debt Instrument [Line Items]
Long-term borrowings	298	300
Genworth Holdings \| 6.52% Senior Notes, Due 2018
Debt Instrument [Line Items]
Long-term borrowings	598	600
Genworth Holdings \| 7.70% Senior Notes, Due 2020
Debt Instrument [Line Items]
Long-term borrowings	397	400
Genworth Holdings \| 7.20% Senior Notes, Due 2021
Debt Instrument [Line Items]
Long-term borrowings	389	399
Genworth Holdings \| 7.625% Senior Notes, Due 2021
Debt Instrument [Line Items]
Long-term borrowings	724	758
Genworth Holdings \| 4.90% Senior Notes, Due 2023
Debt Instrument [Line Items]
Long-term borrowings	399	399
Genworth Holdings \| 4.80% Senior Notes, Due 2024
Debt Instrument [Line Items]
Long-term borrowings	400	400
Genworth Holdings \| 6.50% Senior Notes, Due 2034
Debt Instrument [Line Items]
Long-term borrowings	297	297
Genworth Holdings \| 6.15% Fixed-to-Floating Rate Junior Subordinated Notes, Due 2066
Debt Instrument [Line Items]
Long-term borrowings	598	598
Genworth MI Canada Inc.
Debt Instrument [Line Items]
Long-term borrowings	315	374
Deferred borrowing charges	(2)	(2)
Total	313	372
Genworth MI Canada Inc. \| 5.68% Senior Notes, Due 2020
Debt Instrument [Line Items]
Long-term borrowings	199	236
Genworth MI Canada Inc. \| 4.24% Senior Notes, due 2024
Debt Instrument [Line Items]
Long-term borrowings	116	138
Genworth Financial Mortgage Insurance Pty Limited
Debt Instrument [Line Items]
Long-term borrowings	182	114
Deferred borrowing charges	(4)	(1)
Total	178	113
Genworth Financial Mortgage Insurance Pty Limited \| Floating Rate Junior Notes, Due 2021
Debt Instrument [Line Items]
Long-term borrowings	36	114
Genworth Financial Mortgage Insurance Pty Limited \| Floating Rate Junior Notes, Due 2025
Debt Instrument [Line Items]
Long-term borrowings	$ 146	$ 0

Carrying amount of long-term debt, gross of deferred borrowing charges but net of unamortized discount or premium, including current and noncurrent amounts.

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

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