Quarterly report pursuant to Section 13 or 15(d)

Capital (Details)

v3.19.3
Capital (Details)
$ / shares in Units, $ in Millions
3 Months Ended 9 Months Ended
Mar. 15, 2019
USD ($)
$ / shares
Mar. 16, 2018
USD ($)
$ / shares
Sep. 30, 2019
$ / shares
Sep. 30, 2018
$ / shares
Sep. 30, 2019
$ / shares
shares
Sep. 30, 2018
$ / shares
shares
Class of Stock [Line Items]            
Payments of dividends | $ $ 46.5 $ 31.7        
Dividend paid per sub-share (in dollars per share)     $ 0 $ 0 $ 6.00 $ 4.05
Sub Shares            
Class of Stock [Line Items]            
Ratio of certificates to sub-shares         0.00033333  
Number of shares repurchased and retired (in shares) | shares         6,258 39,768
Cash Dividend | Sub Shares            
Class of Stock [Line Items]            
Dividend paid per sub-share (in dollars per share) $ 1.75 $ 1.05        
Special Dividend | Sub Shares            
Class of Stock [Line Items]            
Dividend paid per sub-share (in dollars per share) $ 4.25 $ 3.00