Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 6,875	$ 7,600
Trade accounts receivable, net	1,040,153	1,051,698
Prepaid expenses and other, net	337,336	443,683
Total current assets	1,384,364	1,502,981
Property and equipment, at cost	5,635,867	5,329,243
Less accumulated depreciation	1,957,782	1,884,132
Net property and equipment	3,678,085	3,445,111
Goodwill and intangible assets, net	193,403	105,157
Other assets	164,887	38,398
Total assets	5,420,739	5,091,647
Current liabilities:
Current portion of long-term debt	0	250,706
Trade accounts payable	640,324	709,736
Claims accruals	277,669	275,139
Accrued payroll	59,282	80,922
Other accrued expenses	84,247	35,845
Total current liabilities	1,061,522	1,352,348
Long-term debt	1,372,143	898,398
Other long-term liabilities	175,656	96,056
Deferred income taxes	676,062	643,461
Stockholders' equity	2,135,356	2,101,384
Total liabilities and stockholders' equity	$ 5,420,739	$ 5,091,647