CONSOLIDATED STATEMENTS OF (LOSS) INCOME AND COMPREHENSIVE (LOSS) INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED STATEMENTS OF (LOSS) INCOME AND COMPREHENSIVE (LOSS) INCOME
Operating revenue	$ 551,138	$ 522,631
Operating expenses:
Salaries, wages and employee benefits	141,590	136,877
Fuel and fuel taxes	38,804	55,096
Depreciation and amortization	41,359	37,193
Insurance and claims	19,855	27,176
Equipment rent	9,382	10,174
Operations and maintenance	35,201	33,310
Purchased transportation	226,716	194,629
Operating taxes and licenses	4,795	4,843
Communications and utilities	3,470	3,488
Loss (gain) on disposal of assets, net	427	(495)
Asset impairments	588	786
Other	16,093	17,239
Total operating expenses	538,280	520,316
Operating income	12,858	2,315
Other expenses:
Interest expense, net	5,605	6,597
Other, net	298	572
Total other expenses, net	5,903	7,169
Income (loss) before income taxes	6,955	(4,854)
Income tax expense (benefit)	2,209	(156)
Consolidated net income (loss) and comprehensive income (loss)	$ 4,746	$ (4,698)
Net earnings (loss) per share:
Average shares outstanding (basic) (in shares)	8,775	8,525
Basic earnings (loss) per share (in dollars per share)	$ 0.54	$ (0.55)
Average shares outstanding (diluted) (in shares)	8,874	8,525
Diluted earnings (loss) per share (in dollars per share)	$ 0.53	$ (0.55)