Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
CURRENT ASSETS:
Cash and cash equivalents	$ 516,031	$ 27,269
Accounts receivable, net	173,408	165,768
Materials and supplies	15,713	14,445
Prepaid expenses and other	16,651	13,332
Deferred income tax assets, net	19,232	19,385
Total current assets	741,035	240,199
PROPERTY AND EQUIPMENT, net	1,769,467	1,643,589
GOODWILL	160,533	160,277
INTANGIBLE ASSETS, net	225,495	230,628
DEFERRED INCOME TAX ASSETS, net	2,462	2,342
OTHER ASSETS, net	21,723	17,122
Total assets	2,920,715	2,294,157
CURRENT LIABILITIES:
Current portion of long-term debt	48,626	57,168
Accounts payable	140,429	134,081
Accrued expenses	73,347	69,097
Deferred income tax liabilities, net	138	925
Total current liabilities	262,540	261,271
LONG-TERM DEBT, less current portion	594,480	569,026
DEFERRED INCOME TAX LIABILITIES, net	315,809	285,780
DEFERRED ITEMS - grants from outside parties	221,502	198,824
CONTINGENT FORWARD SALE CONTRACT	50,106	0
OTHER LONG-TERM LIABILITIES	22,393	18,622
COMMITMENTS AND CONTINGENCIES	0	0
STOCKHOLDERS' EQUITY:
Additional paid-in capital	832,899	385,473
Retained earnings	780,706	741,669
Accumulated other comprehensive income	46,410	37,895
Treasury stock, at cost	(206,722)	(204,952)
Total stockholders' equity	1,453,885	960,634
Total liabilities and stockholders’ equity	2,920,715	2,294,157
Class A common shares [Member]
STOCKHOLDERS' EQUITY:
Common Stock	573	527
Class B common shares [Member]
STOCKHOLDERS' EQUITY:
Common Stock	$ 19	$ 22