Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities
Net income	$ (3,043)	$ 26,106	$ (3,937)
Adjustments to reconcile net income to net cash provided by operating activities:
Early extinguishment of debt		7,753
Impairment of assets held for sale and equity method investments and note receivable	6,793	12,497
Equity in loss of affiliated companies	270	381	1,350
Deferred income tax provision (benefit)	714	5,691	(20,156)
Depreciation and amortization	90,484	90,831	91,340
Losses on sale of equipment	3,853	7,123	2,029
Share based compensation	3,846	2,248	673
Other	660	(2,360)	2,067
Interest paid (received) in kind		(7,516)	1,452
Gain on sale of subsidiary	(831)
Changes in operating assets and liabilities:
Receivables	7,149	(8,972)	(32,051)
Prepaid insurance and licenses	(3,294)	(4,006)	45
Operating supplies	70	725	(510)
Other assets	(7,790)	(3,438)	(529)
Accounts payable and other accrued liabilities	5,572	(21,020)	41,930
Accrued wages and benefits	(704)	6,304	1,691
Net cash provided by operating activities	103,749	112,347	85,394
Investing activities
Payments for purchases of property and equipment	(151,751)	(223,939)	(240,417)
Proceeds from sales of property and equipment	77,966	55,370	32,183
Acquisition of business			(2,219)
Other	(2,000)	2,480	(758)
Sale of subsidiary, net of cash	(5,845)
Net cash used in investing activities	(81,630)	(166,089)	(211,211)
Financing activities
Borrowings under lines of credit	107,300	292,332	387,973
Payments under lines of credit	(107,300)	(321,665)	(358,640)
Borrowings under long-term debt	106,341	362,013	224,102
Payments of long-term debt	(136,228)	(504,180)	(118,834)
Payments of financing costs and original issue discount	(190)	(4,166)	(5,844)
Proceeds from IPO, net of issuance costs		246,616
Payments of long-term consideration for business acquisition	(990)	(1,010)
Purchase of noncontrolling interest	(8,659)
Tax withholding related to net share settlement of restricted stock awards	(44)
Proceeds from issuance of common stock under ESPP	349
Repurchase of membership units		(217)	(523)
Book overdraft	1,313	(3,537)	3,537
Net cash (used in) provided by financing activities	(38,108)	66,186	131,771
Cash included in assets held for sale	11,784	(11,784)
Net change in cash and cash equivalents	(4,205)	660	5,954
Cash and cash equivalents:
Beginning of period	9,892	9,232	3,278
End of period	5,687	9,892	9,232
Supplemental disclosure of cash flow information
Cash paid during the year for interest	21,136	47,406	44,073
Cash paid during the year for income taxes	58	1,603	(208)
Supplemental disclosure of significant noncash investing and financing activities
Lease conversion			34,169
Finance lease additions		439	1,505
Finance lease extinguishments	40	1,146	222
Assumption of debt			5,377
Debt obligations relieved in conjunction with the divestiture of Xpress Internacional	7,109
Financing costs accrued in accounts payable			1,162
Property and equipment amounts accrued in accounts payable	3,552	1,213	1,196
Uncollected proceeds from asset sales	$ 62	$ 2,671	$ 424