Business Combinations (Baxalta Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Millions		12 Months Ended
	Jun. 03, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Goodwill		$ 19,831.7	$ 17,888.2	$ 4,147.8
Baxalta
Current assets:
Cash and cash equivalents		583.2
Accounts receivable		973.3
Inventories		3,974.6
Other current assets		581.3
Total current assets		6,112.4
Property, plant and equipment		5,406.2
Investments		128.2
Goodwill	$ 12,498.6	12,498.6
Other non-current assets		224.7
Total assets		45,737.3
Current liabilities:
Accounts payable and accrued expenses		1,319.2
Other current liabilities		363.4
Long term borrowings and capital leases		5,424.9
Deferred tax liability		5,130.3
Other non-current liabilities		1,105.8
Total liabilities		13,343.6
Fair value of identifiable assets acquired and liabilities assumed		32,393.7
Fair value of purchase consideration	32,393.7	32,393.7
Currently marketed products | Baxalta
Current assets:
Intangible assets	21,165.0	21,165.0
In-Process Research and Development (IPR&D) | Baxalta
Current assets:
Intangible assets	$ 160.0	160.0
Contract based arrangements | Baxalta
Current assets:
Intangible assets		42.2
Preliminary values | Baxalta
Current assets:
Cash and cash equivalents			583.2
Accounts receivable			1,069.7
Inventories			3,893.4
Other current assets			576.0
Total current assets			6,122.3
Property, plant and equipment			5,452.7
Investments			128.2
Goodwill			11,422.4
Other non-current assets			155.0
Total assets			46,047.8
Current liabilities:
Accounts payable and accrued expenses			1,321.9
Other current liabilities			354.4
Long term borrowings and capital leases			5,424.9
Deferred tax liability			5,445.3
Other non-current liabilities			1,103.6
Total liabilities			13,650.1
Fair value of identifiable assets acquired and liabilities assumed			32,397.7
Fair value of purchase consideration			32,397.7
Preliminary values | Currently marketed products | Baxalta
Current assets:
Intangible assets			21,995.0
Preliminary values | In-Process Research and Development (IPR&D) | Baxalta
Current assets:
Intangible assets			730.0
Preliminary values | Contract based arrangements | Baxalta
Current assets:
Intangible assets			$ 42.2
Measurement period adjustments | Baxalta
Current assets:
Cash and cash equivalents		0.0
Accounts receivable		(96.4)
Inventories		81.2
Other current assets		5.3
Total current assets		(9.9)
Property, plant and equipment		(46.5)
Investments		0.0
Goodwill		1,076.2
Other non-current assets		69.7
Total assets		(310.5)
Current liabilities:
Accounts payable and accrued expenses		(2.7)
Other current liabilities		9.0
Long term borrowings and capital leases		0.0
Deferred tax liability		(315.0)
Other non-current liabilities		2.2
Total liabilities		(306.5)
Fair value of identifiable assets acquired and liabilities assumed		(4.0)
Fair value of purchase consideration		(4.0)
Measurement period adjustments | Currently marketed products | Baxalta
Current assets:
Intangible assets		(830.0)
Measurement period adjustments | In-Process Research and Development (IPR&D) | Baxalta
Current assets:
Intangible assets		(570.0)
Measurement period adjustments | Contract based arrangements | Baxalta
Current assets:
Intangible assets		$ 0.0