CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
CURRENT ASSETS:
Cash and cash equivalents	$ 28,557	$ 127,404
Accounts receivable trade, net	583,994	473,608
Accounts receivable other	5,722	4,331
Prepaid taxes	12,088	294
Prepaid expenses and other current assets	25,697	16,653
TOTAL CURRENT ASSETS	656,058	622,290
Restricted investments	24,181	20,877
Property and equipment, net	562,150	438,594
Other intangibles, net	74,348	11,844
Goodwill, net	348,661	262,376
Other assets	5,543	4,278
TOTAL ASSETS	1,670,941	1,360,259
CURRENT LIABILITIES:
Accounts payable trade	338,933	266,555
Accounts payable other	12,268	21,070
Accrued payroll	28,994	36,223
Accrued other	59,305	46,013
Current portion of capital lease	2,777	2,697
Current portion of long-term debt	77,266	45,163
TOTAL CURRENT LIABILITIES	519,543	417,721
Long-term debt	214,808	115,529
Non-current liabilities	37,927	23,595
Long-term portion of capital lease	7,696	10,576
Deferred taxes	121,095	164,659
STOCKHOLDERS' EQUITY:
Preferred stock, $.01 par value; 2,000,000 shares authorized; no shares issued or outstanding in 2017 and 2016
Additional paid-in capital	173,011	173,565
Purchase price in excess of predecessor basis, net of tax benefit of $10,306	(15,458)	(15,458)
Retained earnings	870,716	735,563
Accumulated other comprehensive loss	(194)	(273)
Treasury stock; at cost,7,777,722 shares in 2017 and 8,031,810 shares in 2016	(258,622)	(265,637)
TOTAL STOCKHOLDERS' EQUITY	769,872	628,179
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	1,670,941	1,360,259
Class A Common Stock [Member]
STOCKHOLDERS' EQUITY:
Common stock	412	412
Class B Common Stock [Member]
STOCKHOLDERS' EQUITY:
Common stock	$ 7	$ 7