General form of registration statement for all companies including face-amount certificate companies

Prepaid expenses and other current assets (Q3) (Details)

v3.20.4
Prepaid expenses and other current assets (Q3) (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Mar. 05, 2020
Aug. 28, 2019
Mar. 31, 2020
Sep. 30, 2019
Sep. 30, 2019
Dec. 31, 2019
Sep. 30, 2020
Dec. 31, 2018
Prepaid Expenses and Other Current Assets [Line Items]                
Stock issued to third parties for services (in shares)   1,000,000            
Shares issued to third parties for services   $ 3,400 $ 125 $ 3,440   $ 3,477    
Prepaid advertising   3,400       1,776   $ 0
Advertising expenses incurred         $ 600      
iHeart                
Prepaid Expenses and Other Current Assets [Line Items]                
Committed usage amount of media inventory   $ 1,700       1,700    
Prepaid advertising           2,800 $ 3,000  
Advertising expenses incurred           600    
Prepaid expenses and other current assets | iHeart                
Prepaid Expenses and Other Current Assets [Line Items]                
Prepaid advertising           1,700 1,300  
Other noncurrent assets | iHeart                
Prepaid Expenses and Other Current Assets [Line Items]                
Prepaid advertising           $ 1,100 $ 1,700  
Common Stock                
Prepaid Expenses and Other Current Assets [Line Items]                
Stock issued to third parties for services (in shares)     125,000 1,000,000   1,009,000    
Shares issued to third parties for services       $ 1   $ 1    
Common Stock | iHeart                
Prepaid Expenses and Other Current Assets [Line Items]                
Stock issued to third parties for services (in shares) 125,000 1,000,000            
Shares issued to third parties for services $ 100 $ 3,400