BUSINESS ACQUISITIONS (Details) - USD ($)											12 Months Ended
	Nov. 06, 2018	Sep. 19, 2018	Jun. 18, 2018	Feb. 01, 2018	Dec. 07, 2017	Dec. 01, 2017	Sep. 28, 2017	Jul. 14, 2017	May 01, 2017	Feb. 29, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Total consideration											$ 440,000,000	$ 587,000,000	$ 139,000,000
Goodwill acquired during the year											228,000,000	335,000,000
Goodwill deductible for tax purposes											190,000,000	273,000,000	95,000,000
Finite-lived intangibles											178,000,000	242,000,000	44,000,000
Revenues											84,000,000
Cash acquired from acquisition											6,000,000	12,000,000
Goodwill											$ 6,563,000,000	6,335,000,000	$ 6,000,000,000
Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life											18 years
Mobile Medical Examination Services, Inc. (MedXM) [Member]
Business Acquisition [Line Items]
Total consideration				$ 142,000,000
Goodwill deductible for tax purposes				45,000,000
Finite-lived intangibles				77,000,000
Cash acquired from acquisition				5,000,000
Cash consideration				130,000,000
Goodwill				57,000,000
Working capital				7,000,000
Property, plant and equipment, net				$ 1,000,000
Mobile Medical Examination Services, Inc. (MedXM) [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life				15 years
Mobile Medical Examination Services, Inc. (MedXM) [Member] | Other Operating Income (Expense) [Member]
Business Acquisition [Line Items]
Contingent consideration arrangements											$ (12,000,000)
Mobile Medical Examination Services, Inc. (MedXM) [Member] | Level 3 [Member]
Business Acquisition [Line Items]
Estimated contingent consideration				$ 12,000,000							0
Cape Cod Healthcare, Inc. [Member]
Business Acquisition [Line Items]
Cash consideration			$ 35,000,000
ReproSource, Inc. [Member]
Business Acquisition [Line Items]
Total consideration		$ 35,000,000
Cash consideration		30,000,000
ReproSource, Inc. [Member] | Level 3 [Member]
Business Acquisition [Line Items]
Estimated contingent consideration		$ 5,000,000
Oxford Immunotec, Inc. [Member]
Business Acquisition [Line Items]
Goodwill deductible for tax purposes	$ 99,000,000
Finite-lived intangibles	54,000,000
Cash acquired from acquisition	1,000,000
Cash consideration	170,000,000
Working capital	12,000,000
Property, plant and equipment, net	$ 5,000,000
Oxford Immunotec, Inc. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life	15 years
Oxford Immunotec, Inc. [Member] | Customer Contracts [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life	5 years
PeaceHealth (PHL) [Member]
Business Acquisition [Line Items]
Goodwill deductible for tax purposes									$ 71,000,000
Cash consideration									101,000,000
PeaceHealth (PHL) [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangibles									$ 30,000,000
Finite-lived intangible asset, useful life									15 years
Med Fusion and Clear Point [Member]
Business Acquisition [Line Items]
Goodwill deductible for tax purposes								$ 62,000,000
Cash consideration								150,000,000
Goodwill								64,000,000
Property, plant and equipment, net								31,000,000
Med Fusion and Clear Point [Member] | Capital Lease Obligations [Member]
Business Acquisition [Line Items]
Capital lease obligation								28,000,000
Med Fusion and Clear Point [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangibles								$ 84,000,000
Finite-lived intangible asset, useful life								15 years
The William W. Backus Hospital and The Hospital of Central Connecticut [Member]
Business Acquisition [Line Items]
Cash consideration							$ 30,000,000
Cleveland HeartLab, Inc. (CHL) [Member]
Business Acquisition [Line Items]
Goodwill deductible for tax purposes						$ 1,000,000
Cash acquired from acquisition						12,000,000
Cash consideration						94,000,000
Goodwill						55,000,000
Working capital						4,000,000
Property, plant and equipment, net						3,000,000
Deferred tax assets						11,000,000
Deferred tax liabilities						11,000,000
Cleveland HeartLab, Inc. (CHL) [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangibles						$ 32,000,000
Finite-lived intangible asset, useful life						15 years
Shiel Holdings LLC (Shiel) [Member]
Business Acquisition [Line Items]
Total consideration					$ 176,000,000
Goodwill deductible for tax purposes					100,000,000
Cash consideration					170,000,000
Estimated contingent consideration					6,000,000
Goodwill					106,000,000
Shiel Holdings LLC (Shiel) [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangibles					$ 70,000,000
Finite-lived intangible asset, useful life					15 years
Shiel Holdings LLC (Shiel) [Member] | Level 3 [Member]
Business Acquisition [Line Items]
Estimated contingent consideration											$ 7,000,000	$ 6,000,000
Clinical Laboratory Partners, LLC (CLP) [Member]
Business Acquisition [Line Items]
Goodwill deductible for tax purposes										$ 91,000,000
Cash consideration										135,000,000
Clinical Laboratory Partners, LLC (CLP) [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite-lived intangibles										$ 43,000,000
Finite-lived intangible asset, useful life										15 years