SEGMENT REPORTING - Total Revenues Based on Location of the Customer and Long-Lived Assets by Geographic Regions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Total revenues
Revenues	$ 16,207,106	$ 15,309,508	$ 16,631,172
Long-lived assets
Total long-lived assets	715,371	695,696	405,423
Right-of-use lease assets	319,785	310,860
United States
Total revenues
Revenues	13,896,382	13,143,522	14,370,454
Long-lived assets
Total long-lived assets	551,511	489,129	321,766
Right-of-use lease assets	253,400	216,400
Other locations
Total revenues
Revenues	2,310,724	2,165,986	2,260,718
Long-lived assets
Total long-lived assets	163,860	206,567	$ 83,657
Right-of-use lease assets	$ 66,400	$ 94,400