Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues
Revenue		$ 210,830	$ 220,459	$ 613,333	$ 654,832
Operating expenses:
Salaries, wages, and related expenses		78,812	83,687	235,964	238,281
Fuel expense		18,061	28,812	59,264	85,858
Operations and maintenance		11,912	14,742	36,956	44,814
Revenue equipment rentals and purchased transportation		58,604	50,428	151,677	146,267
Operating taxes and licenses		2,979	3,170	9,555	9,719
Insurance and claims		13,317	14,050	40,491	35,755
Communications and utilities		1,306	1,790	4,657	5,268
General supplies and expenses		7,673	7,584	27,568	21,493
Depreciation and amortization		13,428	20,817	51,274	61,230
Gain on disposition of property and equipment, net		(2,073)	(751)	(7,048)	(959)
Impairment of long lived property, equipment, and right-of-use assets		0	0	26,569	0
Total operating expenses		204,019	224,329	636,927	647,726
Operating income (loss)		6,811	(3,870)	(23,594)	7,106
Interest expense, net		1,935	2,198	5,917	6,048
Income from equity method investment		(1,176)	(2,138)	(971)	(7,548)
Income (loss) before income taxes		6,052	(3,930)	(28,540)	8,606
Income tax expense (benefit)		1,339	112	(7,000)	3,645
Income (loss) from continuing operations		4,713	(4,042)	(21,540)	4,961
Income from discontinued operations, net of tax		2,788	853	4,485	2,354
Net income (loss)		$ 7,501	$ (3,189)	$ (17,055)	$ 7,315
Basic income (loss) per share:
Income (loss) from continuing operations (in dollars per share)		$ 0.28	$ (0.22)	$ (1.24)	$ 0.27
Income from discontinued operations (in dollars per share)		0.16	0.05	0.26	0.13
Net income (loss)(1) (in dollars per share)	[1]	0.44	(0.17)	(0.98)	0.40
Diluted income (loss) per share:
Income (loss) from continuing operations (in dollars per share)		0.27	(0.22)	(1.24)	0.27
Income from discontinued operations (in dollars per share)		0.16	0.05	0.26	0.13
Net income (loss)(1) (in dollars per share)	[1]	$ 0.43	$ (0.17)	$ (0.98)	$ 0.39
Basic weighted average shares outstanding (in shares)		17,134	18,458	17,435	18,426
Diluted weighted average shares outstanding (in shares)		17,267	18,458	17,435	18,620
Cargo and Freight [Member]
Revenues
Revenue		$ 196,217	$ 197,377	$ 565,362	$ 583,950
Fuel Surcharge [Member]
Revenues
Revenue		$ 14,613	$ 23,082	$ 47,971	$ 70,882

[1] Sum of the individual amounts may not add due to rounding.