Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended		12 Months Ended	36 Months Ended
		Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Dec. 31, 2017	Sep. 03, 2018
Restructuring Cost and Reserve [Line Items]
Integration costs	[1]	$ 82	$ 73	$ 202	$ 235
Enterprise-wide Cost Reduction/Productivity Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred				226
Expected restructuring cost		1,200		$ 1,200
Percentage of expected costs to be non-cash				20.00%
Manufacturing Plant Network Optimization [Member] | Enterprise-wide Cost Reduction/Productivity Plan [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost		700		$ 700
Restructuring costs incurred		322		322
Centralization of Corporate and Platform Functions [Member] | Enterprise-wide Cost Reduction/Productivity Plan [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost		450		450
Restructuring costs incurred		$ 252		252
Business Integration Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred				$ 35
Hospira [Member]
Restructuring Cost and Reserve [Line Items]
Integration costs							$ 1,000
Expected integration related costs, period				3 years
Hospira [Member] | Return of Acquired Rights [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred						$ 215
Hospira [Member] | Business Integration Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs incurred				$ 186

[1] Integration costs represent external, incremental costs directly related to integrating acquired businesses, and primarily include expenditures for consulting and the integration of systems and processes. In the third quarter and first nine months of 2018, integration costs were primarily related to our acquisition of Hospira. In the third quarter and first nine months of 2017, integration costs primarily relate to our acquisitions of Hospira and Medivation. The first nine months of 2017 also include a net gain of $12 million related to the settlement of the Hospira U.S. qualified defined benefit pension plan (see Note 10).