Commitments, Guarantees and Contingent Liabilities - Guaranty funds and Guarantees (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Loss Contingencies
Limitations or indemnifications of reinsurance agreements	$ 0
Guaranty Funds
Loss Contingencies
Liability for insurance assessments	12	$ 4
Insurance assessments, premium tax offsets	19	$ 9
Residual guarantee
Loss Contingencies
Potential leased automobiles residual value	$ 27
Guarantee obligations term, low end of range	1 year
Guarantee obligations term, high end of range	4 years

The high end of the range of the approximate term of the guarantee or each group of similar guarantees.

No definition available.

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- Definition

The low end of the range of the approximate term of the guarantee or each group of similar guarantees.

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate expected value at the end of useful life of leased automobiles.

+ References

No definition available.

+ Details

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- Definition

Represents the limitations or indemnifications of reinsurance agreements with regard to insurance risk transfer, and transferred all of the future risks and responsibilities for performance on the underlying variable annuity contracts to prudential, including those related to benefit guarantees.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

The amount of insurance-related assessment liability that is expected to be recovered through a premium tax offset based on current laws applied to in-force policies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 405
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392405&loc=d3e24119-109301

+ Details

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- Definition

The liability as of the balance sheet date representing required funding mandated by statute or regulatory authority that is related directly or indirectly to underwriting activities, including pools for self-insurance and excluding premium taxes and income taxes. The funds derived from the assessments generally enable a government guarantor to pay insurance claims in the event that the underwriting insurer is insolvent or otherwise unable to meet its payment obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 405
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=51828112&loc=d3e23169-109297

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 405
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392405&loc=d3e24119-109301

+ Details

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- Details

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