Jerry Moyes' Retirement (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
Sep. 30, 2016	Mar. 31, 2017
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities, Initiation Date	Sep. 08, 2016
Restructuring and Related Activities, Completion Date	Dec. 31, 2019
Monthly consulting fee	$ 200
One time expense for Jerry Moyes' retirement	7,100
Accrued consulting fees	6,800	$ 0
Impact of equity award modifications	$ 300
Income statement caption included in	"Salaries, wages, and employee benefits

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Date the exit and disposal activities were completed or are expected to be completed, in CCYY-MM-DD format.

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Date the restructuring activities were initiated or are expected to be initiated, in CCYY-MM-DD format.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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