SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Significant Accounting Policies [Line Items]
Restricted cash		$ (359,388)	$ 359,388	$ 0
Property and equipment, depreciation method		Depreciation is computed using the straight-line method over the estimated lives of the assets of 3 to 30 years.
Software
Significant Accounting Policies [Line Items]
Intangible assets, estimated lives (in years)		3 years
Intangible assets, amortization method		We amortize software using the straight-line method over 3 years.
Minimum
Significant Accounting Policies [Line Items]
Property and equipment, estimated lives (in years)		3 years
Intangible assets, estimated lives (in years)		3 years
Restricted shares and restricted units grants, discount for post-vesting holding restrictions (percent)		17.00%
Maximum
Significant Accounting Policies [Line Items]
Property and equipment, estimated lives (in years)		30 years
Intangible assets, estimated lives (in years)		8 years
Restricted shares and restricted units grants, discount for post-vesting holding restrictions (percent)		22.00%
Freightquote
Significant Accounting Policies [Line Items]
Restricted cash	$ 359,400
Truckload Transactions
Significant Accounting Policies [Line Items]
Percentage of truckload transactions that are shared transactions between branches		49.00%
Stock Option
Significant Accounting Policies [Line Items]
Stock award, vesting period (in years)		5 years