Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Depreciation and amortization	$ 348.8	$ 381.5
Revenue	4,683.1	5,602.0
Segment Reporting Information, Income (Loss) before Income Taxes	890.8	1,951.1
Income related to the termination of the exenatide collaboratio	0	495.4
Asset impairment, restructuring, and other special charges	(31.4)	(21.7)
Neuroscience [Member]
Revenue	964.4	1,848.8
Endocrinology [Member]
Revenue	1,639.2	1,724.9
Oncology [Member]
Revenue	764.3	764.2
Cardiovascular [Member]
Revenue	712.8	693.9
Animal health [Member]
Depreciation and amortization	23.6	25.8
Revenue	527.4	499.1
Segment Reporting Information, Income (Loss) before Income Taxes	134.4	129.2
Other pharmaceuticals [Member]
Revenue	75.0	71.1
Pharmaceutical products, total [Member]
Depreciation and amortization	325.2	355.7
Revenue	4,155.7	5,102.9
Segment Reporting Information, Income (Loss) before Income Taxes	787.8	1,348.2
Total segment [Member]
Segment Reporting Information, Income (Loss) before Income Taxes	922.2	1,477.4
Amylin [Member]
Income related to the termination of the exenatide collaboratio	$ 0	$ 495.4