Other (Income) Expense, Net - Narrative (Details) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Component of Other Income / Expense of Nonoperating [Line Items]
Foreign currency devaluation related to Venezuela				$ 0	$ 715
Gain (loss) related to litigation settlement				117
Noncash contribution expense					78
Interest paid				$ 470	452
CGRP receptor antagonists
Component of Other Income / Expense of Nonoperating [Line Items]
Gain (Loss) on disposition of intangible assets	$ 40	$ 250			$ 250
VENEZUELA
Component of Other Income / Expense of Nonoperating [Line Items]
Foreign currency exchange rate, translation		6.30			6.30
Foreign currency devaluation related to Venezuela		$ 138	$ 715