Fair Value Measurements (Details) - Fair Value, Measurements, Nonrecurring [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Losses	$ 4,329	$ 2,377	$ 9,952	$ 8,567
Revenue earning equipment, Trucks [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Losses	1,657	1,527	4,400	4,981
Revenue earning equipment, Tractors [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Losses	2,062	530	3,970	2,824
Revenue earning equipment, Trailers [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Losses	610	320	1,582	762
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale at fair value	18,989	13,785	18,989	13,785
Fair Value, Inputs, Level 3 [Member] | Revenue earning equipment, Trucks [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale at fair value	7,701	8,437	7,701	8,437
Fair Value, Inputs, Level 3 [Member] | Revenue earning equipment, Tractors [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale at fair value	10,093	4,666	10,093	4,666
Fair Value, Inputs, Level 3 [Member] | Revenue earning equipment, Trailers [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale at fair value	$ 1,195	$ 682	$ 1,195	$ 682