BUSINESS SEGMENT INFORMATION (Net Sales of Key Products) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Net product sales									$ 14,045	$ 11,660	$ 12,304
Alliance revenues									2,515	4,219	4,081
Other revenues									107	391	277
Total Revenues	$ 4,287	$ 4,069	$ 4,163	$ 4,041	$ 4,258	$ 3,921	$ 3,889	$ 3,811	16,560	15,879	16,385
Baraclude [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,312	1,441	1,527
Hepatitis C Franchise [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,603	256
Reyataz [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,139	1,362	1,551
Sustiva Franchise [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,252	1,444	1,614
Empliciti [Member]
Segment Reporting Information [Line Items]
Total Revenues									3
Erbitux [Member]
Segment Reporting Information [Line Items]
Total Revenues									501	723	696
Opdivo [Member]
Segment Reporting Information [Line Items]
Total Revenues									942	6
Sprycel [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,620	1,493	1,280
Yervoy [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,126	1,308	960
Abilify [Member]
Segment Reporting Information [Line Items]
Total Revenues									746	2,020	2,289
Orencia [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,885	1,652	1,444
Eliquis [Member]
Segment Reporting Information [Line Items]
Total Revenues									1,860	774	146
Mature Products And All Other [Member]
Segment Reporting Information [Line Items]
Total Revenues									2,571	3,400	4,878
Alliance Partners [Member]
Segment Reporting Information [Line Items]
Net product sales									4,308	3,531	4,417
Alliance revenues									2,408	3,828	3,804
Total Revenues									$ 6,716	$ 7,359	$ 8,221