v3.20.4
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) (Parenthetical) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Class A common stock | Dividend declared      
Cash dividend declared (in dollars per share) $ 0.03 $ 0.20 $ 0.20
Class A common stock | Special dividends      
Cash dividend declared (in dollars per share)     1.55
Class B common stock | Dividend declared      
Cash dividend declared (in dollars per share) $ 0.03 $ 0.20 0.20
Class B common stock | Special dividends      
Cash dividend declared (in dollars per share)     $ 1.55