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
OPERATING REVENUES:
Operating revenues	$ 121,942	$ 128,994	$ 344,075	$ 390,680
OPERATING EXPENSES AND COSTS:
Salaries, wages and benefits	30,618	32,920	90,991	94,586
Operating supplies and expenses	20,875	25,455	62,866	73,487
Rent and purchased transportation	41,402	40,740	114,688	128,647
Depreciation	13,403	14,173	41,936	40,974
Insurance and claims	3,145	3,697	5,701	11,872
Other	2,599	3,788	10,411	10,321
(Gain) Loss on sale or disposition of equipment	(174)	688	(71)	362
Total operating expenses and costs	111,868	121,461	326,522	360,249
OPERATING INCOME	10,074	7,533	17,553	30,431
NON-OPERATING (EXPENSE) INCOME	(94)	490	(6,209)	3,765
INTEREST EXPENSE	(2,211)	(2,178)	(6,601)	(6,277)
INCOME BEFORE INCOME TAXES	7,769	5,845	4,743	27,919
FEDERAL AND STATE INCOME TAX EXPENSE:
Current	106	106	106	302
Deferred	1,663	1,158	763	6,081
Total federal and state income tax expense	1,769	1,264	869	6,383
NET INCOME	$ 6,000	$ 4,581	$ 3,874	$ 21,536
INCOME PER COMMON SHARE:
Basic (in dollars per share)	$ 1.04	$ 0.80	$ 0.67	$ 3.68
Diluted (in dollars per share)	$ 1.04	$ 0.79	$ 0.67	$ 3.65
AVERAGE COMMON SHARES OUTSTANDING:
Basic (in shares)	5,763	5,756	5,758	5,859
Diluted (in shares)	5,768	5,799	5,775	5,907
Freight Transportation Service [Member]
OPERATING REVENUES:
Operating revenues	$ 109,854	$ 110,149	$ 307,441	$ 332,846
Fuel Surcharge [Member]
OPERATING REVENUES:
Operating revenues	$ 12,088	$ 18,845	$ 36,634	$ 57,834