Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 35,000	$ 7,600
Trade accounts receivable, net	1,011,829	1,051,698
Other receivables, net	230,331	274,511
Inventories	21,106	21,977
Prepaid expenses	183,033	147,195
Total current assets	1,481,299	1,502,981
Property and equipment, at cost:
Revenue and service equipment	4,837,747	4,716,860
Land	58,692	49,486
Structures and improvements	302,184	238,202
Furniture and office equipment	442,183	324,695
Total property and equipment	5,640,806	5,329,243
Less accumulated depreciation	2,019,940	1,884,132
Net property and equipment	3,620,866	3,445,111
Goodwill	96,326	40,087
Other intangible assets, net	106,506	65,070
Other assets	165,857	38,398
Total assets	5,470,854	5,091,647
Current liabilities:
Current portion of long-term debt	0	250,706
Trade accounts payable	602,601	709,736
Claims accruals	279,590	275,139
Accrued payroll	68,220	80,922
Other accrued expenses	85,355	35,845
Total current liabilities	1,035,766	1,352,348
Long-term debt	1,295,740	898,398
Other long-term liabilities	173,241	96,056
Deferred income taxes	699,078	643,461
Total liabilities	3,203,825	2,990,263
Commitments and contingencies (Note 10)
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, 2019 and 2018, of which 106,212,908 and 108,710,825 shares were outstanding at December 31, 2019 and 2018, respectively)	1,671	1,671
Additional paid-in capital	374,049	340,457
Retained earnings	4,592,938	4,188,435
Treasury stock, at cost (60,886,524 shares at December 31, 2019, and 58,388,607 shares at December 31, 2018)	(2,701,629)	(2,429,179)
Total stockholders’ equity	2,267,029	2,101,384
Total liabilities and stockholders' equity	$ 5,470,854	$ 5,091,647