Quarterly report pursuant to Section 13 or 15(d)

Consolidated Statements of Stockholders' Equity (Parenthetical)

v3.24.1
Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Jan. 19, 2024
Feb. 29, 2024
Feb. 28, 2023
Feb. 29, 2024
Feb. 28, 2023
Unrealized gains (losses) on securities, tax   $ 6.3 $ (3.3) $ 3.5 $ (23.3)
Reclassification adjustment for realized gains (loss) on securities, tax   $ 0.0 $ 0.0 $ 0.0 $ 0.0
Cash dividends declared, per share   $ 0.89 $ 0.79 $ 2.67 $ 2.37
Authorized In January 2024 [Member]          
Expiration date       Jan. 31, 2024  
Authorized In January 2024 [Member] | Maximum [Member]          
Approved repurchase amount   $ 400.0   $ 400.0  
Authorized In January 19 2024 [Member]          
Expiration date May 31, 2027        
Authorized In January 19 2024 [Member] | Maximum [Member]          
Approved repurchase amount $ 400.0