Operating Information by Segment and Geographic Area - External Revenue and Total Assets by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 3,103,085	$ 3,456,938	$ 9,278,017	$ 10,889,575
North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	2,023,600	2,320,600	6,058,900	7,079,800
Asia Pacific (includes Australia)
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	255,300	329,500	1,001,400	980,900
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	417,700	491,300	1,052,300	1,594,400
Central and South America
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	337,400	190,900	904,800	823,700
Middle East and Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 69,100	$ 124,600	$ 260,600	$ 410,800