COMMITMENTS AND CONTINGENT LIABILITIES - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2017	Sep. 30, 2018
Commitments And Contingencies Disclosure [Line Items]
Loss contingency accrual, insurance-related assessment, discount rate	4.25%
Loss contingency, discounted amount of insurance-related assessment liability	$ 62
Loss contingency, undiscounted amount of insurance-related assessment liability	94
Loss contingency, insurance-related assessment, discounted amount of premium tax offset	48
Loss contingency, insurance-related assessment, undiscounted amount of premium tax offset	74
Loss contingency, loss in period	$ 14
Loss contingency, discounted amount of insurance-related assessment liability, realization period for associated asset offsets (in years)		four years

Commitments and Contingencies Disclosure [Line Items]

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The rate applied as of the balance sheet date to reduce the undiscounted amount of a guarantee fund and other insurance-related assessments to present value.

+ References

+ Details

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- Definition

The present value of 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

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- Definition

The period of time over which the assets related to premium tax offsets and policy surcharges are expected to be realized.

+ References

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- Definition

The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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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://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 405
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=99384745&loc=d3e23169-109297

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