Property, plant and equipment (Tables)

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

Property, plant and equipment

Property, plant and equipment consisted of the following (dollar amounts in millions):

		December 31,
	Useful life (in years)	2015			2014
Land	—	$	319		$	398
Buildings and improvements	10-40	3,638			3,612
Manufacturing equipment	8-12	2,051			1,711
Laboratory equipment	8-12	1,140			1,240
Other	3-15	4,278			4,112
Construction in progress	—	746			1,183
Property, plant and equipment, gross		12,172			12,256
Less accumulated depreciation and amortization		(7,265		)	(7,033		)
Property, plant and equipment, net		$	4,907		$	5,223