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

Debt - Fair value (Q1) (Details)

v3.21.1
Debt - Fair value (Q1) (Details) - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Dec. 31, 2019
Debt Disclosure [Abstract]        
Interest expense $ 0.8 $ 2.3 $ 9.2 $ 0.7
November 2019 Notes        
Debt Instrument [Line Items]        
Debt fair value 2.6   2.5  
Senior Seller Notes        
Debt Instrument [Line Items]        
Debt fair value 9.5   9.0  
Junior Seller Notes        
Debt Instrument [Line Items]        
Debt fair value 4.7   4.5  
ABG Notes        
Debt Instrument [Line Items]        
Debt fair value 0.6   0.5  
June 2020 Notes        
Debt Instrument [Line Items]        
Debt fair value $ 1.3   $ 1.3