CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
CURRENT ASSETS:
Cash and cash equivalents	$ 203,173	$ 168,729
Accounts receivable trade	456,619	450,451
Allowance for uncollectible trade accounts	(8,500)	(6,912)
Other receivables	1,028	3,237
Prepaid taxes	708	630
Prepaid expenses and other current assets	13,682	24,086
TOTAL CURRENT ASSETS	666,710	640,221
Restricted investments	20,961	22,601
Property and equipment, net	650,990	663,165
Right-of-use assets - operating leases	35,889	35,548
Right-of-use assets - financing leases	4,704	5,865
Other intangibles, net	114,128	120,967
Goodwill, net	484,350	484,459
Other assets	21,445	18,748
TOTAL ASSETS	1,999,177	1,991,574
CURRENT LIABILITIES:
Accounts payable trade	257,752	257,247
Accounts payable other	16,049	11,585
Accrued payroll	29,835	45,540
Accrued other	89,696	86,686
Lease liability - operating leases	8,760	8,567
Lease liability - financing leases	3,061	3,048
Current portion of long term debt	90,948	94,691
TOTAL CURRENT LIABILITIES	496,101	507,364
Long term debt	167,857	186,934
Non-current liabilities	41,424	36,355
Lease liability - operating leases	28,662	28,518
Lease liability - financing leases	278	1,820
Deferred taxes	159,018	155,304
STOCKHOLDERS' EQUITY:
Preferred stock: $.01 par value; 2,000,000 shares authorized; no shares issued or outstanding in 2020 and 2019
Additional paid-in capital	178,914	179,637
Purchase price in excess of predecessor basis, net of tax benefit of $10,306	(15,458)	(15,458)
Retained earnings	1,205,991	1,179,601
Accumulated other comprehensive loss	(283)	(186)
Treasury stock; at cost, 7,706,638 shares in 2020 and 7,870,888 shares in 2019	(263,746)	(268,734)
TOTAL STOCKHOLDERS' EQUITY	1,105,837	1,075,279
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	1,999,177	1,991,574
Class A Common Stock [Member]
STOCKHOLDERS' EQUITY:
Common stock	412	412
Class B Common Stock [Member]
STOCKHOLDERS' EQUITY:
Common stock	$ 7	$ 7