Financial Information Related to Guarantor Subsidiaries (Details) (USD $) In Thousands	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009
Current assets:
Cash and cash equivalents	$ 244,114		$ 50,727	$ 64,049		$ 206,505
Short-term investment	164,161
Accounts receivable, net	437,954		452,450
Income taxes receivable	0		0
Prepaid expenses	38,862		25,828
Inventory and other current assets	220,410		235,047
Intercompany interest receivable	0		0
Total current assets	1,105,501		764,052
Property, plant and equipment, net	1,394,918		1,313,150
Goodwill, net	589,761		588,000
Notes receivable	71,261		69,026
Intercompany notes receivable	0		0
Investments in subsidiaries	0		0
Equity-method investments	63,308		59,322
Intangible and other long-term assets, net	136,888		113,983
Total assets	3,361,637		2,907,533
Current liabilities:
Accounts payable	109,167		110,276
Accrued expenses	170,383		162,044
Income taxes payable	8,955		2,475
Deferred income taxes	24,027		29,353
Current portion of decommissioning liabilities	17,172		16,929	22,232
Current maturities of long-term debt	391,262		184,810
Intercompany interest payable	0		0
Total current liabilities	720,966		505,887
Deferred income taxes	228,191		223,936
Decommissioning liabilities	103,880		100,787	107,686
Long-term debt, net	810,184		681,635
Intercompany Notes Payable	0		0
Intercompany payables/(receivables)	0		0
Other long-term liabilities	121,800		114,737
Stockholders' equity:
Preferred stock of $.01 par value	0		0
Common stock of $.001 par value	80		79
Additional paid in capital	439,164		415,278
Accumulated other comprehensive loss, net	(17,134)	(17,845)	(25,700)	(31,464)	(28,695)	(18,996)
Retained earnings (accumulated deficit)	954,506		890,894
Total stockholders' equity	1,376,616		1,280,551
Total liabilities and stockholders' equity	3,361,637		2,907,533
Parent [Member]
Current assets:
Cash and cash equivalents	0		0	0		0
Short-term investment	0
Accounts receivable, net	0		0
Income taxes receivable	0		0
Prepaid expenses	89		18
Inventory and other current assets	0		0
Intercompany interest receivable	0		0
Total current assets	89		18
Property, plant and equipment, net	0		0
Goodwill, net	0		0
Notes receivable	0		0
Intercompany notes receivable	0		0
Investments in subsidiaries	124,271		124,271
Equity-method investments	0		0
Intangible and other long-term assets, net	0		0
Total assets	124,360		124,289
Current liabilities:
Accounts payable	0		0
Accrued expenses	115		153
Income taxes payable	14,494		4,499
Deferred income taxes	22,374		29,353
Current portion of decommissioning liabilities	0		0
Current maturities of long-term debt	0		0
Intercompany interest payable	0		0
Total current liabilities	36,983		34,005
Deferred income taxes	215,691		211,173
Decommissioning liabilities	0		0
Long-term debt, net	0		0
Intercompany Notes Payable	0		0
Intercompany payables/(receivables)	(99,845)		(100,882)
Other long-term liabilities	8,260		8,260
Stockholders' equity:
Preferred stock of $.01 par value	0		0
Common stock of $.001 par value	80		79
Additional paid in capital	439,164		415,278
Accumulated other comprehensive loss, net	0		0
Retained earnings (accumulated deficit)	(475,973)		(443,624)
Total stockholders' equity	(36,729)		(28,267)
Total liabilities and stockholders' equity	124,360		124,289
Issuer [Member]
Current assets:
Cash and cash equivalents	185,133		0	861		171,903
Short-term investment	164,161
Accounts receivable, net	241		415
Income taxes receivable	0		0
Prepaid expenses	7,589		4,128
Inventory and other current assets	1,427		1,678
Intercompany interest receivable	28,694		15,883
Total current assets	387,245		22,104
Property, plant and equipment, net	2,956		3,189
Goodwill, net	0		0
Notes receivable	0		0
Intercompany notes receivable	488,637		456,280
Investments in subsidiaries	593,994		602,461
Equity-method investments	61,476		43,947
Intangible and other long-term assets, net	30,867		22,455
Total assets	1,565,175		1,150,436
Current liabilities:
Accounts payable	4,144		6,654
Accrued expenses	38,736		42,821
Income taxes payable	0		0
Deferred income taxes	0		0
Current portion of decommissioning liabilities	0		0
Current maturities of long-term debt	390,452		184,000
Intercompany interest payable	0		0
Total current liabilities	433,332		233,475
Deferred income taxes	0		0
Decommissioning liabilities	0		0
Long-term debt, net	798,043		669,089
Intercompany Notes Payable	0		0
Intercompany payables/(receivables)	897,383		760,164
Other long-term liabilities	38,599		37,537
Stockholders' equity:
Preferred stock of $.01 par value	0		0
Common stock of $.001 par value	0		0
Additional paid in capital	124,271		124,271
Accumulated other comprehensive loss, net	0		0
Retained earnings (accumulated deficit)	(726,453)		(674,100)
Total stockholders' equity	(602,182)		(549,829)
Total liabilities and stockholders' equity	1,565,175		1,150,436
Guarantor Subsidiaries [Member]
Current assets:
Cash and cash equivalents	4,729		5,493	3,518		4,871
Short-term investment	0
Accounts receivable, net	371,205		382,935
Income taxes receivable	0		0
Prepaid expenses	15,639		8,948
Inventory and other current assets	207,035		222,822
Intercompany interest receivable	0		0
Total current assets	598,608		620,198
Property, plant and equipment, net	1,007,942		957,561
Goodwill, net	446,947		447,467
Notes receivable	71,261		69,026
Intercompany notes receivable	0		0
Investments in subsidiaries	0		4,347
Equity-method investments	0		0
Intangible and other long-term assets, net	77,593		61,722
Total assets	2,202,351		2,160,321
Current liabilities:
Accounts payable	75,462		71,790
Accrued expenses	88,677		91,451
Income taxes payable	0		0
Deferred income taxes	0		0
Current portion of decommissioning liabilities	17,172		16,929
Current maturities of long-term debt	0		0
Intercompany interest payable	0		0
Total current liabilities	181,311		180,170
Deferred income taxes	0		0
Decommissioning liabilities	103,880		100,787
Long-term debt, net	0		0
Intercompany Notes Payable	0		0
Intercompany payables/(receivables)	(139,540)		(1,407)
Other long-term liabilities	27,138		19,427
Stockholders' equity:
Preferred stock of $.01 par value	0		4,347
Common stock of $.001 par value	0		0
Additional paid in capital	0		0
Accumulated other comprehensive loss, net	0		0
Retained earnings (accumulated deficit)	2,029,562		1,856,997
Total stockholders' equity	2,029,562		1,861,344
Total liabilities and stockholders' equity	2,202,351		2,160,321
Non-Guarantor Subsidiaries [Member]
Current assets:
Cash and cash equivalents	54,252		45,234	59,670		29,731
Short-term investment	0
Accounts receivable, net	104,847		99,010
Income taxes receivable	5,539		2,024
Prepaid expenses	15,545		12,734
Inventory and other current assets	11,948		10,547
Intercompany interest receivable	0		0
Total current assets	192,131		169,549
Property, plant and equipment, net	384,020		352,400
Goodwill, net	142,814		140,233
Notes receivable	0		0
Intercompany notes receivable	0		0
Investments in subsidiaries	0		4,347
Equity-method investments	1,832		15,375
Intangible and other long-term assets, net	28,428		29,806
Total assets	749,225		712,010
Current liabilities:
Accounts payable	68,434		64,636
Accrued expenses	42,855		27,619
Income taxes payable	0		0
Deferred income taxes	1,653		0
Current portion of decommissioning liabilities	0		0
Current maturities of long-term debt	810		810
Intercompany interest payable	28,694		15,883
Total current liabilities	142,446		108,948
Deferred income taxes	12,500		12,763
Decommissioning liabilities	0		0
Long-term debt, net	12,141		12,546
Intercompany Notes Payable	488,637		456,280
Intercompany payables/(receivables)	(123,009)		(125,246)
Other long-term liabilities	47,803		49,513
Stockholders' equity:
Preferred stock of $.01 par value	0		4,347
Common stock of $.001 par value	403		176
Additional paid in capital	58,068		66,762
Accumulated other comprehensive loss, net	(17,134)		(25,700)
Retained earnings (accumulated deficit)	127,370		151,621
Total stockholders' equity	168,707		197,206
Total liabilities and stockholders' equity	749,225		712,010
Consolidation, Eliminations [Member]
Current assets:
Cash and cash equivalents	0		0
Short-term investment	0
Accounts receivable, net	(38,339)		(29,910)
Income taxes receivable	(5,539)		(2,024)
Prepaid expenses	0		0
Inventory and other current assets	0		0
Intercompany interest receivable	(28,694)		(15,883)
Total current assets	(72,572)		(47,817)
Property, plant and equipment, net	0		0
Goodwill, net	0		0
Notes receivable	0		0
Intercompany notes receivable	(488,637)		(456,280)
Investments in subsidiaries	(718,265)		(735,426)
Equity-method investments	0		0
Intangible and other long-term assets, net	0		0
Total assets	(1,279,474)		(1,239,253)
Current liabilities:
Accounts payable	(38,873)		(32,804)
Accrued expenses	0		0
Income taxes payable	(5,539)		(2,024)
Deferred income taxes	0		0
Current portion of decommissioning liabilities	0		0
Current maturities of long-term debt	0		0
Intercompany interest payable	(28,694)		(15,883)
Total current liabilities	(73,106)		(50,711)
Deferred income taxes	0		0
Decommissioning liabilities	0		0
Long-term debt, net	0		0
Intercompany Notes Payable	(488,637)		(456,280)
Intercompany payables/(receivables)	(534,989)		(532,629)
Other long-term liabilities	0		0
Stockholders' equity:
Preferred stock of $.01 par value	0		(8,694)
Common stock of $.001 par value	(403)		(176)
Additional paid in capital	(182,339)		(191,033)
Accumulated other comprehensive loss, net	0		0
Retained earnings (accumulated deficit)	0		0
Total stockholders' equity	(182,742)		(199,903)
Total liabilities and stockholders' equity	$ (1,279,474)		$ (1,239,523)