Income Taxes (Tax Effects of Temporary Differences That Give Rise to Significant Portions of Deferred Tax Assets and Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Noncurrent deferred tax assets:
Accounts receivable	$ 1,422	$ 1,849
Advertising relationships	2,548	3,686
Other liabilities	27,014	28,140
AMT tax credit	2,042	2,042
Net operating loss	111,778	155,475
Noncurrent deferred tax assets	144,804	191,192
Less: valuation allowance	(17,205)	(17,173)
Net noncurrent deferred tax assets	127,599	174,019
Noncurrent deferred tax liabilities:
Intangible assets	482,620	527,775
Property and equipment	20,485	30,260
Cancellation of debt income	12,544	31,865
Noncurrent deferred tax liabilities	515,649	589,900
Net noncurrent deferred tax liabilities	388,050	415,881
Net deferred tax liabilities	$ 388,050	$ 415,881