Summary of Intangible Assets Acquired (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended	0 Months Ended
Dec. 31, 2013	Dec. 12, 2013 Affiliate relationships WestwoodOne Acquisition	Nov. 14, 2013 Advertising relationships Townsquare Transaction
Business Acquisition [Line Items]
Estimated Useful Life in Years		9 years	5 years
Fair Value	$ 152,522	$ 150,900	$ 552

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

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