BENEFITS PAYABLE - Benefit Expenses Excluded From Activity in Benefits Payable (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Premium deficiency reserve - Individual Commercial	$ 0	$ 13
Military services	0	3
Individual Commercial	(23)	(30)
Total	(23)	(14)
Operating Segments \| Individual Commercial
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Individual Commercial	(33)	(40)
Other Businesses
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Individual Commercial	$ 10	$ 10

Benefit expenses associated with military services and provisions associated with future policy benefits

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- Definition

Health Care Reform, Provision for Premium Deficiency1

+ References

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- Definition

Expense recorded during the period related to benefit expenses associated with military services

+ References

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.

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- Definition

Amount of expense (income) recognized due to changes in the accrued obligation to policyholders that relates to insured events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437

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