Other Information - Barter and Trade Revenues and Expenses from Continuing Operations (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Barter and trade revenues	$ 46.3	$ 32.7
Barter and trade expenses	34.3	$ 28.8
Advertising Exchanged for Equity Interests [Member]
Barter and trade revenues	11.7
Barter and trade expenses	$ 0.0

Total revenue recognized from advertising barter transactions for each income statement presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=51667831&loc=d3e49171-111630

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration