Income Taxes Reconciliation (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Computed at federal statutory rate	$ (60,652)	$ (77,374)	$ (37,862)
State income taxes, net of federal income tax benefit	(8,026)	(4,825)	(1,927)
Other, net	(24)	(5,956)	(3,062)
Income Tax Expense (Benefit), Continuing Operations, Total	$ (68,702)	$ (88,155)	$ (42,851)
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Computed at federal statutory rate	(35.00%)	(35.00%)	(35.00%)
State income taxes, net of federal income tax benefit	(4.60%)	(2.20%)	(1.80%)
Other, net	0.00%	(2.70%)	(2.80%)
Effective Income Tax Rate, Continuing Operations, Total	(39.60%)	(39.90%)	(39.60%)