CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
REVENUES	$ 500,180	$ 547,039
COSTS AND EXPENSES:
Direct operating costs (excluding items below)	204,832	255,734
Depreciation and amortization	98,852	89,690
Selling, general and administrative	26,930	27,586
Loss (gain) on disposals of property and equipment	2,177	(513)
Total costs and expenses	332,791	372,497
INCOME FROM OPERATIONS	167,389	174,542
OTHER INCOME (EXPENSE):
Interest expense, net of interest capitalized	(38,924)	(32,746)
Gain on extinguishment of debt	577	0
Interest income	444	155
Other - net	(2,577)	(1,041)
Total other income (expense) - net	(40,480)	(33,632)
INCOME BEFORE INCOME TAXES	126,909	140,910
Provision for income taxes	4,110	17,241
NET INCOME	$ 122,799	$ 123,669
NET INCOME PER SHARE - BASIC (in dollars per share)	$ 0.98	$ 0.99
NET INCOME PER SHARE - DILUTED (in dollars per share)	0.98	0.99
CASH DIVIDENDS DECLARED PER SHARE (in dollars per share)	$ 0	$ 0.1