Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 51,927	$ 355,549
Trade accounts receivable, net	1,528,075	1,506,619
Other receivables	330,764	216,615
Inventories	40,602	25,032
Prepaid expenses and other current assets	260,410	209,554
Total current assets	2,211,778	2,313,369
Property and equipment, at cost:
Revenue and service equipment	6,815,776	5,667,131
Land	88,699	67,540
Structures and improvements	382,007	318,222
Software, office equipment and furniture	712,998	627,423
Total property and equipment	7,999,480	6,680,316
Less accumulated depreciation	3,019,663	2,612,661
Net property and equipment	4,979,817	4,067,655
Goodwill	120,449	100,521
Other intangible assets, net	115,941	90,572
Other assets	358,597	222,231
Total assets	7,786,582	6,794,348
Current liabilities:
Current portion of long-term debt	0	355,972
Trade accounts payable	798,776	772,736
Claims accruals	452,149	307,210
Accrued payroll and payroll taxes	188,252	190,950
Other accrued expenses	129,054	102,732
Total current liabilities	1,568,231	1,729,600
Long-term debt	1,261,738	945,257
Other long-term liabilities	369,314	256,233
Deferred income taxes	920,531	745,442
Total liabilities	4,119,814	3,676,532
Stockholders’ equity:
Preferred stock, $100 par value. 10 million shares authorized; none outstanding	0	0
Common stock, $.01 par value. 1 billion shares authorized; (167,099,432 shares issued at December 31, 2022 and 2021, of which 103,743,382 and 105,093,706 shares were outstanding at December 31, 2022 and 2021, respectively)	1,671	1,671
Additional paid-in capital	499,897	448,217
Retained earnings	6,423,730	5,621,103
Treasury stock, at cost (63,356,050 shares at December 31, 2022, and 62,005,726 shares at December 31, 2021)	(3,258,530)	(2,953,175)
Total stockholders’ equity	3,666,768	3,117,816
Total liabilities and stockholders' equity	$ 7,786,582	$ 6,794,348