Business Segment Information - Financial Information Regarding Company's Operations by Geographic Area (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 3,357,540	$ 1,901,864
Directly related cost of transportation and other expenses	[1]	2,406,004	1,286,728
Salaries and other operating expenses	[2]	566,021	456,081
Operating income		385,515	159,055
Identifiable assets at period end		5,454,997	3,509,967	$ 4,927,503
Capital expenditures		8,391	6,127
Equity		2,878,650	2,037,145	$ 2,663,227	$ 2,197,219
Operating Segments | United States Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		875,392	650,407
Directly related cost of transportation and other expenses	[1]	502,637	373,961
Salaries and other operating expenses	[2]	238,698	225,944
Operating income		134,057	50,502
Identifiable assets at period end		2,747,984	1,858,250
Capital expenditures		3,025	4,497
Equity		1,985,265	1,369,580
Operating Segments | Other North America Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		94,858	81,831
Directly related cost of transportation and other expenses	[1]	53,791	45,890
Salaries and other operating expenses	[2]	25,737	23,712
Operating income		15,330	12,229
Identifiable assets at period end		194,050	135,810
Capital expenditures		122	61
Equity		73,066	63,378
Operating Segments | Latin America Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		44,864	37,890
Directly related cost of transportation and other expenses	[1]	26,700	23,765
Salaries and other operating expenses	[2]	12,377	11,749
Operating income		5,787	2,376
Identifiable assets at period end		93,072	68,402
Capital expenditures		53	102
Equity		32,632	28,020
Operating Segments | North Asia Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		1,325,621	537,955
Directly related cost of transportation and other expenses	[1]	1,084,102	425,301
Salaries and other operating expenses	[2]	106,920	57,433
Operating income		134,599	55,221
Identifiable assets at period end		988,954	512,808
Capital expenditures		357	325
Equity		342,233	237,255
Operating Segments | South Asia Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		363,682	169,042
Directly related cost of transportation and other expenses	[1]	283,860	121,282
Salaries and other operating expenses	[2]	43,165	29,908
Operating income		36,657	17,852
Identifiable assets at period end		331,271	179,508
Capital expenditures		579	188
Equity		148,293	102,001
Operating Segments | Europe Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		493,718	320,640
Directly related cost of transportation and other expenses	[1]	334,294	221,998
Salaries and other operating expenses	[2]	109,455	81,854
Operating income		49,969	16,788
Identifiable assets at period end		853,944	554,831
Capital expenditures		3,554	645
Equity		218,198	159,222
Operating Segments | Middle East Africa and India Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		160,609	105,039
Directly related cost of transportation and other expenses	[1]	121,212	74,976
Salaries and other operating expenses	[2]	30,275	25,950
Operating income		9,122	4,113
Identifiable assets at period end		265,495	200,382
Capital expenditures		701	309
Equity		121,040	113,349
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		(1,204)	(940)
Directly related cost of transportation and other expenses	[1]	(592)	(445)
Salaries and other operating expenses	[2]	(606)	(469)
Operating income		(6)	(26)
Identifiable assets at period end		(19,773)	(24)
Equity		$ (42,077)	$ (35,660)

[1] Directly related cost of transportation and other expenses totals operating expenses from airfreight services, ocean freight and ocean services and customs brokerage and other services as shown in the condensed consolidated statements of earnings.

[2] Salaries and other operating expenses totals salaries and related, rent and occupancy, depreciation and amortization, selling and promotion and other as shown in the condensed consolidated statements of earnings.