EMPLOYEE STOCK BENEFIT PLANS (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 45	$ 120	$ 140	$ 202
Income tax benefit	13	38	47	66
Unrecognized compensation cost	255		255
Weighted-average period over which unrecognized compensation cost is expected to be recognized			2 years 6 months 0 days
Stock Options [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense		(1)	1	4
Restricted Stock [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	19	9	56	46
Number of shares granted			2.4
Weighted average grant date fair value of grants during the period			$ 37.76
Vesting period of stock-based compensation award, in years			4
Market share units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	5	4	21	17
Number of shares granted			1.0
Weighted average grant date fair value of grants during the period			$ 37.40
Vesting period of stock-based compensation award, in years			4
Performance share units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	21	14	62	41
Number of shares granted			2.5
Weighted average grant date fair value of grants during the period			$ 37.40
Vesting period of stock-based compensation award, in years			3
Amylin Stock Options And Restricted Stock Units [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense		$ 94		$ 94