Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current Assets:
Cash and cash equivalents	$ 81	$ 1,539
Accounts receivable, net	172,119	135,083
Prepaid expenses and other	28,399	29,857
Total current assets	200,599	166,479
Property and Equipment, at cost	1,260,856	1,101,946
Less-accumulated depreciation	538,065	497,827
Net property and equipment	722,791	604,119
Goodwill and Identifiable Intangibles, net	24,368	25,398
Other Noncurrent Assets	4,961	4,374
Total assets	952,719	800,370
Current Liabilities:
Accounts payable	63,742	45,149
Wages, vacation and employees’ benefits	44,140	31,700
Claims and insurance accruals	37,704	33,047
Other current liabilities	20,841	18,286
Current portion of long-term debt	17,072	16,762
Total current liabilities	183,499	144,944
Other Liabilities:
Long-term debt, less current portion	110,161	57,042
Deferred income taxes	90,064	80,199
Claims, insurance and other	37,242	35,107
Total other liabilities	237,467	172,348
Commitments and Contingencies
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, 25,490,381 and 25,322,701 shares issued and outstanding at September 30, 2017 and December 31, 2016, respectively	25	25
Additional paid-in-capital	243,382	237,846
Deferred compensation trust, 170,900 and 166,807 shares of common stock at cost at September 30, 2017 and December 31, 2016, respectively	(3,448)	(3,190)
Retained earnings	291,794	248,397
Total stockholders’ equity	531,753	483,078
Total liabilities and stockholders’ equity	$ 952,719	$ 800,370