Income Taxes (Summary of Income Tax Benefit (Provision)) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Income Tax Disclosure [Line Items]
Total current income tax benefit (provision)	$ 53,587	$ (12,055)	$ 51,408	$ (17,408)
Total deferred income tax provision	(21,827)	(5,170)	(28,700)	(35,599)
Total income tax benefit (provision)	31,760	(17,225)	22,708	(53,007)
Income tax provision included in income from discontinued operations	(4,856)	(1,797)	(16,449)	(25,628)
Income tax benefit (provision) on income from continuing operations	$ 36,616	$ (15,428)	$ 39,157	$ (27,379)