Summary of Significant Accounting Policies - Schedule of Convertible Equity Shares Excluded from Calculation of Diluted Net Loss per Share (Details) shares in Thousands	6 Months Ended
	Jun. 30, 2020 shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded from calculation of diluted net loss per share	9,757
Convertible Promissory Note | Emmis
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded from calculation of diluted net loss per share	1,238
Convertible Promissory Note | SG Broadcasting
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded from calculation of diluted net loss per share	2,785
Series A Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded from calculation of diluted net loss per share	5,734