Revenues (Revenue by Geographic Location) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 38,297	$ 38,944	$ 79,456	$ 75,283
Hedging gains (losses)	151	108	200	245
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	17,999	17,863	36,869	34,395
EMEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	11,363	12,313	24,208	23,981
APAC
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	6,945	6,536	14,183	12,632
Other Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 1,839	$ 2,124	$ 3,996	$ 4,030
Geographic Concentration Risk | Revenue Benchmark
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue	100.00%	100.00%	100.00%	100.00%
Geographic Concentration Risk | Revenue Benchmark | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue	47.00%	46.00%	47.00%	46.00%
Geographic Concentration Risk | Revenue Benchmark | EMEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue	30.00%	32.00%	30.00%	32.00%
Geographic Concentration Risk | Revenue Benchmark | APAC
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue	18.00%	17.00%	18.00%	17.00%
Geographic Concentration Risk | Revenue Benchmark | Other Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of total revenue	5.00%	5.00%	5.00%	5.00%