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

Stockholders' Equity (Details)

v3.21.2
Stockholders' Equity (Details)
$ / shares in Units, shares in Thousands, $ in Thousands
 12 Months Ended
Mar. 29, 2021
Oct. 27, 2020
USD ($)
$ / shares
shares
Sep. 14, 2020
shares
Dec. 31, 2020
USD ($)
shares
Sep. 30, 2021
shares
Dec. 31, 2019
shares
Proceeds from Series A preferred stock issuance, net of issuance costs | $       $ 346,150    
Stock split, conversion ratio 0.333          
Common stock, shares issued       140,222 158,524 139,721
Common stock, shares outstanding       125,074 158,474 139,721
Common stock, shares authorized       700,000 1,000,000 700,000
Preferred stock, shares authorized       61,006 100,000 0
Preferred stock, shares issued       61,006 0 0
Preferred stock, shares outstanding       61,006 0 0
Treasury stock, shares       15,146 50 0
Series A Preferred Stock            
Purchase price | $       $ 85,464    
Preferred Purchase Agreement            
Number of shares issued   15,568        
Exchange of common stock for Series A preferred stock (in shares)   45,438        
Dividend declared (in dollars per share) | $ / shares   $ 0        
Stock split, conversion ratio   1        
Preferred Purchase Agreement | Series A Preferred Stock            
Number of shares issued   61,006        
Purchase price | $   $ 350,000        
Proceeds from Series A preferred stock issuance, net of issuance costs | $   $ 89,300        
2017 Equity Plan            
Common stock issued under employee purchase plan (in shares)     61