Summary of Prelimnary Purchase Price Allocation (Detail) (USD $)	Sep. 25, 2012	Dec. 31, 2011	Dec. 31, 2012 KCHZ Acquisition	Dec. 06, 2012 KCHZ Acquisition
Schedule of Business Acquisitions, Purchase Price Allocation [Line Items]
Current assets			$ 61
Property and equipment		1,790,000	841
Other assets			13
Broadcast Licenses			8,453
Goodwill		4,342,000	1,895
Current liabilities			(97)
Total purchase price	$ 16,800,000	$ 17,394,000	$ 11,166	$ 11,200,000

Business Acquisition, Purchase Price Allocation, Broadcast Licenses

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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The amount of acquisition cost of a business combination allocated to current assets.

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The amount of acquisition cost of a business combination allocated to current liabilities of the acquired entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

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-Name Emerging Issues Task Force (EITF)

-Number 98-1

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 52

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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Amount of acquisition cost of a business combination allocated to other assets not separately disclosed in the balance sheet.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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