Income Tax - Reconciliation of Income Tax (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Income Tax Reconciliation [Line Items]
Tax expense at statutory rate, Amount	$ 99,062		$ 39,116		$ (788,143)
State income taxes, Amount	(3,107)		6,584		(49,180)
Tax-free disposition of investment, Amount	(145,524)
Uncertain tax position, Amount	6,106
Sale of unconsolidated affiliate, Amount	(545)		40,411
Nondeductible goodwill, Amount					305,657
Other, Amount	1,683		1,834		8,111
Total income tax expense (benefit)	$ (42,325)	[1]	$ 87,945	[2]	$ (523,555)	[3]
Tax expense at statutory rate, Percentage	35.00%		35.00%		35.00%
State income taxes, Percentage	(1.10%)		5.90%		2.20%
Tax-free disposition of investment, Percentage	(51.40%)
Uncertain tax position, Percentage	2.20%
Sale of unconsolidated affiliate, Percentage	(0.20%)		36.20%
Nondeductible goodwill, Percentage					(13.50%)
Other, Percentage	0.60%		1.60%		(0.40%)
Total, Percentage	(14.90%)		78.70%		23.30%

[1] Excludes $431.0 million in income tax expense related to discontinued operations.

[2] Excludes $80.4 million in income tax expense related to discontinued operations.

[3] Excludes $67.2 million in income tax expense related to discontinued operations.