CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2016
Cash flows from operating activities
Net income (loss)			$ 12,688	$ (11,852)
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation	$ 25,527	$ 16,196	48,815	31,069
Amortization of intangible assets	6,239	1,442	8,133	2,884
Amortization of deferred financing fees	800	500	1,452	793
Write-off of deferred financing fees				3,883
Stock-based compensation expense			1,788	538
Deferred taxes			(16,239)	(1,419)
Bad debt expense			202	221
Non-cash interest expense				92
Gain on disposition of property and equipment			(645)	(157)
Gain on disposition of building			(836)
Deferred gain recognized on sales-type leases	(900)	(200)	(1,414)	(339)
Impairment	2,840		2,840
Changes in operating assets and liabilities
Accounts receivable			(31,460)	(20,311)
Drivers’ advances and other receivables			(95)	102
Payments received on sales-type leases			6,547	2,076
Prepaid and other current assets			(6,315)	433
Accounts payable			56	1,103
Accrued expenses and other liabilities			3,518	4,714
Net cash provided by operating activities			29,035	13,830
Cash flows from investing activities
Purchase of property and equipment			(31,123)	(6,806)
Proceeds from sale of property and equipment			11,676	2,952
Cash paid in acquisitions, net of cash acquired			(79,084)	(40,571)
Net cash used in investing activities			(98,531)	(44,425)
Cash flows from financing activities:
Advances on line of credit			468,130	343,083
Repayments on line of credit			(472,691)	(349,939)
Advances on long-term debt			5,901
Principal payments on and payoff of long-term debt			(25,227)	(224,587)
Proceeds from Term Loan Facility				289,500
Deferred financing fees			(633)	(14,266)
Pay off of subordinated debt				(66,715)
Proceeds from issuance of common stock			84,569	64,577
Repurchase of common stock				(36,168)
Exercise of options			50
Net cash provided by financing activities			57,621	68,469
Effect of exchange rates on cash and cash equivalents			(70)	15
Net (decrease) increase in cash and cash equivalents			(11,945)		$ 37,889
Cash and cash equivalents – beginning of period			90,679
Cash and cash equivalents – beginning of period			90,679	3,695
Cash and cash equivalents – end of period	78,734		78,734
Cash and cash equivalents – end of period	78,734	41,584	78,734	41,584	$ 3,695
Supplemental disclosure of cash flow information
Cash paid for interest			20,025	17,728
Cash paid for income taxes			1,347	436
Noncash investing and financing activities
Property and equipment acquired with debt or capital lease obligations			11,589	5,139
Accrued capital expenditures			4,362
Property and equipment sold for notes receivable			248	70
Property and equipment transferred to sales-type lease			3,932	4,842
Sales-type lease returns to property and equipment			407	645
Sales-type lease assets acquired with debt or capital lease obligations			9,873
Sales-type lease assets sold for notes receivable			28,147	12,700
Sales-type lease returns to sales-type lease assets			15,451	6,957
Common stock issued in acquisition	$ 15,355	3,438	15,355	3,438
Issuance of earnout shares			48,200
Series A
Cash flows from financing activities:
Issuance of convertible preferred stock				(65,000)
Convertible preferred stock dividends			$ (2,478)
Noncash investing and financing activities
Accrued convertible preferred dividends		$ 1,693		1,693
Series B
Cash flows from financing activities:
Convertible preferred stock dividends				$ (2,016)