Quarterly report pursuant to Section 13 or 15(d)

Impairment of Goodwill and Other Indefinite-Lived Intangible Assets - Fair Value Measurement Inputs and Valuation Techniques (Detail)

v3.10.0.1
Impairment of Goodwill and Other Indefinite-Lived Intangible Assets - Fair Value Measurement Inputs and Valuation Techniques (Detail) - Broadcast Licenses [Member]
Sep. 30, 2018
Measurement Input, Long-term Revenue Growth Rate [Member]  
Goodwill And Other Intangible Assets [Line Items]  
Derivative asset measurement input percentage 1.9
Measurement Input, Risk-adjusted Discount Rate [Member]  
Goodwill And Other Intangible Assets [Line Items]  
Derivative asset measurement input percentage 9.0
Minimum [Member] | Measurement Input, Operating Profit Margin [Member]  
Goodwill And Other Intangible Assets [Line Items]  
Derivative asset measurement input percentage (13.9)
Maximum [Member] | Measurement Input, Operating Profit Margin [Member]  
Goodwill And Other Intangible Assets [Line Items]  
Derivative asset measurement input percentage 30.8