Revenue Earning Equipment Level 3 Fair Value Measurement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue Earning Equipment [Line Items]
Total Losses	$ 25,666	$ 12,551	$ 37,217	$ 19,839
Net book value of assets held for sale not exceeding fair value	88,000	60,000	88,000	60,000
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring
Revenue Earning Equipment [Line Items]
Assets held for sale	35,604	68,559	35,604	68,559
Total Losses	25,666	12,551	37,217	19,839
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring | Trucks
Revenue Earning Equipment [Line Items]
Assets held for sale	9,026	13,749	9,026	13,749
Total Losses	10,927	2,570	16,727	4,314
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring | Tractors
Revenue Earning Equipment [Line Items]
Assets held for sale	23,726	51,795	23,726	51,795
Total Losses	12,134	9,206	17,317	14,088
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring | Trailers
Revenue Earning Equipment [Line Items]
Assets held for sale	2,852	3,015	2,852	3,015
Total Losses	$ 2,605	$ 775	$ 3,173	$ 1,437