ACQUISITION - ALLOCATION OF PURCHASE PRICE (Details) - USD ($) $ in Millions		Dec. 31, 2019	Jun. 30, 2019	Nov. 30, 2018
Business Acquisition [Line Items]
Goodwill		$ 39,998	$ 40,273
PHC-MERCK ACQUISITION [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets				$ 421
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment				119
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill				2,134
Goodwill				2,083
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets				209
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets				4,966
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities				232
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent				763
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities				94
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities				1,089
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value	[1]			169
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net				$ 3,708
Minority Interest Ownership Percentage				48.00%

[1] Represents a 48% minority ownership interest in the Merck India company.