Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from EPS Calculation (Details)

v3.8.0.1
Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Anti-dilutive Securities Excluded from EPS Calculation (Details) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 3 Months Ended 9 Months Ended
Jul. 27, 2016
Mar. 31, 2017
Aug. 31, 2016
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
UMG Recordings | Common Stock              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock issued during period, litigation (in shares)     1,800,000        
Emerging Markets Communications LLC              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Deferred compensation to be paid $ 25,000            
Restricted stock units              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Antidilutive securities excluded from computation of earnings per share (in shares)       1,143,000 147,000 1,458,000 253,000
Equity warrants              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Antidilutive securities excluded from computation of earnings per share (in shares)       0 1,163,000 471,000 1,163,000
Public SPAC Warrants              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Antidilutive securities excluded from computation of earnings per share (in shares)       6,173,000 6,173,000 6,173,000 6,173,000
Convertible notes              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Antidilutive securities excluded from computation of earnings per share (in shares)       4,447,000 4,447,000 4,447,000 4,447,000
EMC deferred consideration              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Antidilutive securities excluded from computation of earnings per share (in shares)       1,439,000 0 3,737,000 503,000
Contingently issuable shares              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Antidilutive securities excluded from computation of earnings per share (in shares)       900,000 509,000 900,000 171,000
Price Per Share Scenario One | UMG Recordings - share price threshold | Common Stock              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock issued during period, litigation (in shares)           500,000  
Price Per Share Scenario One | UMG Recordings | Common Stock              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock issued during period, litigation (in shares)   500,000 500,000.0        
Share price of common stock (in usd per share)   $ 10.00 $ 10 $ 10.00   $ 10.00  
Price Per Share Scenario Two | UMG Recordings - share price threshold | Common Stock              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock issued during period, litigation (in shares)           400,000  
Price Per Share Scenario Two | UMG Recordings | Common Stock              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Stock issued during period, litigation (in shares)   400,000 400,000.0        
Share price of common stock (in usd per share)   $ 12.00 $ 12 $ 12.00   $ 12.00  
Public SPAC Warrants | Quotes Prices in Active Markets (Level 1)              
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]              
Number of warrants (in shares)       6,173,228   6,173,228