CONDENSED CONSOLIDATED STATEMENTS OF INCOME (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
CONSOLIDATED STATEMENTS OF INCOME (Abstract)
REVENUES	$ 394,238	$ 333,477
COSTS AND EXPENSES:
Direct operating costs (excluding items below)	209,469	182,139
Depreciation and amortization	64,616	58,966
Selling, general and administrative	29,431	23,056
Loss (gain) on disposals of property and equipment	308	(56)
Material charges and other operating expenses	0	4,571
Total costs and expenses	303,824	268,676
INCOME FROM OPERATIONS	90,414	64,801
OTHER INCOME (EXPENSE):
Interest expense, net of interest capitalized	(18,581)	(11,257)
Interest income	359	114
Other - net	(794)	1,337
Total other income (expense) - net	(19,016)	(9,806)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	71,398	54,995
Provision (benefit) for income taxes	3,264	(504)
NET INCOME FROM CONTINUING OPERATIONS	68,134	55,499
DISCONTINUED OPERATIONS
Income (loss) from discontinued operations, net of tax	0	(5,982)
NET INCOME	$ 68,134	$ 49,517
INCOME PER SHARE - BASIC:
Income from continuing operations (in dollars per share)	$ 0.55	$ 0.45
Discontinued operations (in dollars per share)	$ 0	$ (0.05)
Net income (in dollars per share)	$ 0.55	$ 0.40
INCOME (LOSS) PER SHARE - DILUTED:
Income from continuing operations (in dollars per share)	$ 0.55	$ 0.45
Discontinued operations (in dollars per share)	$ 0	$ (0.05)
Net income (in dollars per share)	$ 0.55	$ 0.40