GOODWILL AND OTHER INTANGIBLE ASSETS - Changes in Carrying Amount of Goodwill by Reportable Segments (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Beginning balance	$ 3,265	$ 3,231
Acquisitions	7	35
Dispositions		(1)
Ending balance	3,272	3,265
Retail
Goodwill [Roll Forward]
Beginning balance	1,059	1,059
Acquisitions	0	0
Dispositions		0
Ending balance	1,059	1,059
Group and Specialty
Goodwill [Roll Forward]
Beginning balance	261	261
Acquisitions	0	0
Dispositions		0
Ending balance	261	261
Healthcare Services
Goodwill [Roll Forward]
Beginning balance	1,945	1,911
Acquisitions	7	35
Dispositions		(1)
Ending balance	$ 1,952	$ 1,945

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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