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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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Summary of Significant Accounting Policies (Narrative) (Detail) - Entity [Domain] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Impairment		$ 10,684
Other than temporary impairment for available for sale securities	$ 0	0	$ 4,600
Advertising expenses	103,000	$ 133,700	$ 113,400
International Outdoor Advertising [Member]
Impairment	$ 10,700
Minimum [Member]
Percentage of ownership	20.00%
Minimum [Member] \| Building and Improvements [Member]
Useful life	10 years
Minimum [Member] \| Structures [Member]
Useful life	5 years
Minimum [Member] \| Towers, Transmitters and Studio Equipment [Member]
Useful life	7 years
Minimum [Member] \| Furniture and other equipment [Member]
Useful life	3 years
Maximum [Member]
Percentage of ownership	50.00%
Maximum [Member] \| Building and Improvements [Member]
Useful life	39 years
Maximum [Member] \| Structures [Member]
Useful life	15 years
Maximum [Member] \| Towers, Transmitters and Studio Equipment [Member]
Useful life	20 years
Maximum [Member] \| Furniture and other equipment [Member]
Useful life	20 years