Tax Effects of Temporary Differences That Give Rise to Significant Portions of Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current deferred tax assets:
Accounts receivable	$ 1,613	$ 3,293
Accrued expenses and other current liabilities	1,896	3,454
Net operating loss	45,564
Current deferred tax assets	49,073	6,747
Less: valuation allowance	(23,928)	(2,975)
Net current deferred tax assets	25,145	3,772
Noncurrent deferred tax assets:
Intangible and other assets	43,185	96,525
Property and equipment	6,207
Advertising relationships	10,689	21,126
Other liabilities	12,216	54,330
Net operating loss	238,176	259,940
Noncurrent deferred tax assets	310,473	431,921
Less: valuation allowance	(147,125)	(198,263)
Net noncurrent deferred tax assets	163,348	233,658
Noncurrent deferred tax liabilities:
Intangible assets	570,856	632,484
Property and equipment	54,465	54,814
Cancellation of debt income	94,257	98,151
Other	3,688	4,980
Noncurrent deferred tax liabilities	723,266	790,429
Net noncurrent deferred tax liabilities	559,918	556,771
Net deferred tax liabilities	$ 534,773	$ 552,999