Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current Assets:
Cash and cash equivalents	$ 137,871	$ 106,588
Accounts receivable, net	357,052	276,755
Income tax receivable	9,412	0
Prepaid expenses and other	32,041	32,912
Total current assets	536,376	416,255
Property and Equipment, at cost	2,277,527	2,144,528
Less: accumulated depreciation	924,628	864,074
Net property and equipment	1,352,899	1,280,454
Operating Lease Right-of-Use Assets	105,376	107,781
Goodwill and Identifiable Intangibles, net	18,576	19,157
Other Noncurrent Assets	34,628	21,603
Total assets	2,047,855	1,845,250
Current Liabilities:
Accounts payable	145,298	114,010
Wages, vacation and employees’ benefits	78,945	73,109
Claims and insurance accruals	49,222	54,717
Other current liabilities	25,594	38,551
Current portion of long-term debt	17,935	19,396
Current portion of operating lease liability	22,155	21,565
Total current liabilities	339,149	321,348
Other Liabilities:
Long-term debt, less current portion	21,360	31,008
Operating lease liability, less current portion	85,522	88,409
Deferred income taxes	123,229	124,137
Claims, insurance and other	74,833	60,015
Total other liabilities	304,944	303,569
Stockholders’ Equity:
Preferred stock, $0.001 par value, 50,000 shares authorized, none issued and outstanding	0	0
Common stock, $0.001 par value, 100,000,000 shares authorized, 26,411,736 and 26,336,589 shares issued and outstanding at June 30, 2022 and December 31,2021, respectively	26	26
Additional paid-in-capital	271,395	274,633
Deferred compensation trust, 83,197 and 94,627 shares of common stock at cost at June 30, 2022 and December 31, 2021, respectively	(6,103)	(4,101)
Retained earnings	1,138,444	949,775
Total stockholders’ equity	1,403,762	1,220,333
Total liabilities and stockholders’ equity	$ 2,047,855	$ 1,845,250