Business Segment Information - Financial Information Regarding Company's Operations by Geographic Area (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	$ 2,074,855	$ 2,090,947	$ 6,130,485	$ 5,902,768
Directly related cost of transportation and other expenses	[2]	1,400,499	1,429,633	4,140,320	3,963,070
Salaries and other operating expenses	[3]	467,806	458,160	1,403,813	1,360,142
Operating income		206,550	203,154	586,352	579,556
Identifiable assets at period end		3,706,453	3,334,800	3,706,453	3,334,800		$ 3,314,559
Capital expenditures		15,521	11,733	37,943	37,642
Equity		2,209,287	1,957,332	2,209,287	1,957,332	$ 2,052,394	$ 1,987,720	$ 1,892,559	$ 1,994,373
Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	(889)	(73,654)	(2,371)	(213,508)
Directly related cost of transportation and other expenses	[2]	(446)	(73,037)	(1,468)	(211,931)
Salaries and other operating expenses	[3]	(438)	(624)	(884)	(1,592)
Operating income		(5)	7	(19)	15
Identifiable assets at period end		2,499	(6,504)	2,499	(6,504)
Equity		(31,737)	(31,360)	(31,737)	(31,360)
Operating Segments | United States Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	692,229	629,043	2,033,088	1,790,869
Directly related cost of transportation and other expenses	[2]	389,254	345,236	1,142,701	957,997
Salaries and other operating expenses	[3]	210,767	204,240	636,243	620,029
Operating income		92,208	79,567	254,144	212,843
Identifiable assets at period end		2,059,345	1,694,556	2,059,345	1,694,556
Capital expenditures		7,644	6,889	23,544	16,092
Equity		1,578,682	1,334,952	1,578,682	1,334,952
Operating Segments | Other North America Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	88,088	92,875	265,035	257,206
Directly related cost of transportation and other expenses	[2]	51,420	58,464	157,997	157,599
Salaries and other operating expenses	[3]	25,731	23,935	76,283	70,036
Operating income		10,937	10,476	30,755	29,571
Identifiable assets at period end		128,336	174,402	128,336	174,402
Capital expenditures		513	301	1,509	4,020
Equity		60,526	66,399	60,526	66,399
Operating Segments | Latin America Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	38,341	43,443	111,277	122,170
Directly related cost of transportation and other expenses	[2]	22,990	27,635	64,149	75,694
Salaries and other operating expenses	[3]	14,547	13,399	41,342	38,996
Operating income		804	2,409	5,786	7,480
Identifiable assets at period end		72,029	53,322	72,029	53,322
Capital expenditures		833	227	1,071	899
Equity		27,217	25,663	27,217	25,663
Operating Segments | North Asia Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	624,351	748,589	1,879,155	2,065,405
Directly related cost of transportation and other expenses	[2]	489,195	601,699	1,475,395	1,640,724
Salaries and other operating expenses	[3]	70,410	74,067	208,781	211,576
Operating income		64,746	72,823	194,979	213,105
Identifiable assets at period end		489,322	540,465	489,322	540,465
Capital expenditures		523	1,280	1,167	2,623
Equity		216,061	197,939	216,061	197,939
Operating Segments | South Asia Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	196,569	205,392	555,128	560,070
Directly related cost of transportation and other expenses	[2]	145,345	158,226	407,642	423,612
Salaries and other operating expenses	[3]	32,482	31,623	97,324	92,409
Operating income		18,742	15,543	50,162	44,049
Identifiable assets at period end		164,976	156,887	164,976	156,887
Capital expenditures		631	910	1,235	1,934
Equity		77,733	86,048	77,733	86,048
Operating Segments | Europe Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	320,769	327,212	952,790	977,967
Directly related cost of transportation and other expenses	[2]	221,149	227,418	657,720	677,167
Salaries and other operating expenses	[3]	86,156	84,136	258,339	248,906
Operating income		13,464	15,658	36,731	51,894
Identifiable assets at period end		563,289	508,855	563,289	508,855
Capital expenditures		5,119	751	8,015	9,167
Equity		169,450	157,973	169,450	157,973
Operating Segments | Middle East Africa And India Segment
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	[1]	115,397	118,047	336,383	342,589
Directly related cost of transportation and other expenses	[2]	81,592	83,992	236,184	242,208
Salaries and other operating expenses	[3]	28,151	27,384	86,385	79,782
Operating income		5,654	6,671	13,814	20,599
Identifiable assets at period end		226,657	212,817	226,657	212,817
Capital expenditures		258	1,375	1,402	2,907
Equity		$ 111,355	$ 119,718	$ 111,355	$ 119,718

[1] In 2019, the Company revised its process to record the transfer, between its geographic operating segments, of revenues and the directly related cost of transportation and other expenses for freight service transactions between Company origin and destination locations. This change better aligns revenue reporting with the location where the services are performed, as well as the transactional reporting being developed as part of the Company’s new accounting systems and processes. The change in presentation had no impact on consolidated or segment operating income. The 2019 results also include the effect of changing the presentation of certain import services from a net to a gross basis, which increased segment revenues and directly related operating expenses but did not change operating income. The impact of these changes on reported segment revenues was immaterial and prior year segment revenues have not been revised.

[2] 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.

[3] 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.