Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current Assets:
Cash and cash equivalents	$ 121,702	$ 25,308
Accounts receivable, net	295,862	216,899
Income tax receivable		96
Prepaid expenses and other	33,045	29,393
Total current assets	450,609	271,696
Property and Equipment, at cost	2,048,419	1,901,244
Less: accumulated depreciation	846,195	765,217
Net property and equipment	1,202,224	1,136,027
Operating Lease Right-of-Use Assets	104,989	113,715
Goodwill and Identifiable Intangibles, net	19,448	20,321
Other Noncurrent Assets	11,989	7,015
Total assets	1,789,259	1,548,774
Current Liabilities:
Accounts payable	140,774	89,381
Wages, vacation and employees’ benefits	77,538	55,392
Claims and insurance accruals	42,622	49,613
Other current liabilities	37,345	40,571
Current portion of long-term debt	20,245	20,588
Current portion of operating lease liability	20,097	20,209
Total current liabilities	338,621	275,754
Other Liabilities:
Long-term debt, less current portion	34,926	50,388
Operating lease liability, less current portion	86,979	95,321
Deferred income taxes	124,903	119,818
Claims, insurance and other	59,104	46,205
Total other liabilities	305,912	311,732
Stockholders’ Equity:
Preferred stock, $0.001 par value, 50,000 shares authorized, none issued and outstanding
Common stock, $0.001 par value, 50,000,000 shares authorized, 26,336,589 and 26,236,570 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively	26	26
Additional paid-in-capital	272,545	267,666
Deferred compensation trust, 95,438 and 91,888 shares of common stock at cost at September 30, 2021 and December 31, 2020, respectively	(3,859)	(2,944)
Retained earnings	876,014	696,540
Total stockholders’ equity	1,144,726	961,288
Total liabilities and stockholders’ equity	$ 1,789,259	$ 1,548,774