Consolidated Statements of Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues
Revenue	$ 432,568	$ 415,363
Operating expenses
Salaries, wages, and benefits	135,394	124,563
Fuel and fuel taxes	40,323	46,904
Vehicle rents	21,877	18,976
Depreciation and amortization, net of (gain) loss on sale of property	25,803	23,062
Operating expenses and supplies	29,674	27,945
Insurance premiums and claims	26,023	24,353
Operating taxes and licenses	3,677	3,173
Communications and utilities	2,452	2,265
General and other operating expenses	21,259	17,479
Total operating expenses	436,236	402,725
Operating income	(3,668)	12,638
Other expense (income)
Interest expense, net	5,421	5,603
Loss on sale of equity method investment	2,000
Equity in loss of affiliated companies		89
Other, net		26
Nonoperating Income (Expense), Total	(7,421)	(5,718)
Income (loss) before income tax provision	(11,089)	6,920
Income tax provision (benefit)	(1,857)	1,901
Net total and comprehensive income (loss)	(9,232)	5,019
Net total and comprehensive income (loss) attributable to noncontrolling interest	(16)	298
Net total and comprehensive income(loss) attributable to controlling interest	$ (9,216)	$ 4,721
Earnings (loss) per share
Basic earnings (loss) per share (in dollars per share)	$ (0.19)	$ 0.10
Basic weighted average shares outstanding (in shares)	49,217	48,394
Diluted earnings (loss) per share (in dollars per share)	$ (0.19)	$ 0.10
Diluted weighted average shares outstanding (in shares)	49,217	49,391
Cargo and Freight [Member]
Revenues
Revenue	$ 392,820	$ 375,312
Fuel Surcharge [Member]
Revenues
Revenue	39,748	40,051
Shipping and Handling [Member]
Operating expenses
Purchased transportation	$ 129,754	$ 114,005