BUSINESS SEGMENT INFORMATION (Net Sales of Key Products) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net sales	$ 3,831	$ 5,251
Baraclude [Member]
Segment Reporting Information [Line Items]
Net sales	366	325	241
Reyataz [Member]
Segment Reporting Information [Line Items]
Net sales	361	358
Sustiva Franchise [Member]
Segment Reporting Information [Line Items]
Net sales	387	386
Erbitux [Member]
Segment Reporting Information [Line Items]
Net sales	162	179
Sprycel [Member]
Segment Reporting Information [Line Items]
Net sales	287	231
Yervoy [Member]
Segment Reporting Information [Line Items]
Net sales	229	154
Abilify [Member]
Segment Reporting Information [Line Items]
Net sales	522	621
Bydureon [Member]
Segment Reporting Information [Line Items]
Net sales	52
Byetta [Member]
Segment Reporting Information [Line Items]
Net sales	85
Forxiga [Member]
Segment Reporting Information [Line Items]
Net sales	3
Onglyza Kombiglyze [Member]
Segment Reporting Information [Line Items]
Net sales	202	161
Nulojix [Member]
Segment Reporting Information [Line Items]
Net sales	5	1
Orencia [Member]
Segment Reporting Information [Line Items]
Net sales	320	254
Avapro Avalide [Member]
Segment Reporting Information [Line Items]
Net sales	46	207
Eliquis [Member]
Segment Reporting Information [Line Items]
Net sales	22
Plavix [Member]
Segment Reporting Information [Line Items]
Net sales	91	1,693
Mature Products And All Other [Member]
Segment Reporting Information [Line Items]
Net sales	$ 691	$ 681