REVENUE FROM CONTRACTS WITH CUSTOMERS - Summary of Gross Revenues Disaggregated by Major Service Line and Timing of Revenue (Details) - USD ($)
$ in Thousands

REVENUE FROM CONTRACTS WITH CUSTOMERS - Summary of Gross Revenues Disaggregated by Major Service Line and Timing of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	$ 4,276,037	$ 3,710,018	$ 8,201,364	$ 7,125,143
NAST
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	3,014,221	2,493,794	5,800,777	4,854,200
Global Forwarding
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	632,472	536,260	1,195,590	1,013,191
Robinson Fresh
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	671,155	696,672	1,269,970	1,280,457
All Other and Corporate
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	162,403	146,314	326,795	289,832
Transportation and logistics services
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	3,953,139	3,319,995	7,590,779	6,422,038
Sourcing
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	322,898	390,023	610,585	703,105
Operating Segments
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	4,276,037	3,710,018	8,201,364	7,125,143
Operating Segments \| NAST
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	2,878,904	2,381,551	5,541,915	4,640,803
Operating Segments \| Global Forwarding
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	617,597	528,820	1,171,351	997,608
Operating Segments \| Robinson Fresh
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	621,024	657,003	1,171,493	1,207,448
Operating Segments \| All Other and Corporate
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	158,512	$ 142,644	316,605	$ 279,284
Operating Segments \| Transportation and logistics services
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	3,953,139		7,590,779
Operating Segments \| Transportation and logistics services \| Performance obligations completed over time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	3,953,139		7,590,779
Operating Segments \| Transportation and logistics services \| NAST
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	2,878,904		5,541,915
Operating Segments \| Transportation and logistics services \| NAST \| Performance obligations completed over time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	2,878,904		5,541,915
Operating Segments \| Transportation and logistics services \| Global Forwarding
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	617,597		1,171,351
Operating Segments \| Transportation and logistics services \| Global Forwarding \| Performance obligations completed over time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	617,597		1,171,351
Operating Segments \| Transportation and logistics services \| Robinson Fresh
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	298,126		560,908
Operating Segments \| Transportation and logistics services \| Robinson Fresh \| Performance obligations completed over time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	298,126		560,908
Operating Segments \| Transportation and logistics services \| All Other and Corporate
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	158,512		316,605
Operating Segments \| Transportation and logistics services \| All Other and Corporate \| Performance obligations completed over time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	158,512		316,605
Operating Segments \| Sourcing
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	322,898		610,585
Operating Segments \| Sourcing \| Performance obligations completed at a point in time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	322,898		610,585
Operating Segments \| Sourcing \| NAST
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	0		0
Operating Segments \| Sourcing \| NAST \| Performance obligations completed at a point in time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	0		0
Operating Segments \| Sourcing \| Global Forwarding
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	0		0
Operating Segments \| Sourcing \| Global Forwarding \| Performance obligations completed at a point in time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	0		0
Operating Segments \| Sourcing \| Robinson Fresh
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	322,898		610,585
Operating Segments \| Sourcing \| Robinson Fresh \| Performance obligations completed at a point in time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	322,898		610,585
Operating Segments \| Sourcing \| All Other and Corporate
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	0		0
Operating Segments \| Sourcing \| All Other and Corporate \| Performance obligations completed at a point in time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenues	$ 0		$ 0