Segment Information - Net Sales Attributed to Countries Representing Significant Portion of Consolidated (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 60,453	$ 43,744	$ 37,955	$ 35,714	$ 43,741	$ 32,714	$ 30,404	$ 29,128	$ 177,866	$ 135,987	$ 107,006
United States
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales									120,486	90,349	70,537
Germany
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales									16,951	14,148	11,816
United Kingdom
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales									11,372	9,547	9,033
Japan
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales									11,907	10,797	8,264
Rest of world
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales									$ 17,150	$ 11,146	$ 7,356