v3.26.1
Income Taxes - Reconciliation of effective income tax amount and rate (Details) - USD ($)
$ in Millions
12 Months Ended
May 31, 2026
May 31, 2025
May 31, 2024
Amount      
Income tax expense at the U.S. federal statutory rate $ 51.6    
State income taxes, net of federal benefit $ 9.6    
Effective Income Tax Rate Reconciliation, State and Local Jurisdiction, Contribution Greater than 50 Percent, Tax Effect [Extensible Enumeration] stpr:FL, stpr:IL    
Foreign tax effects $ 0.1    
Nontaxable or nondeductible items:      
Bargain purchase gain (6.2)    
Compensation 2.6    
Other 1.9    
Tax benefit from stock-based compensation (1.4)    
Income Tax Expense (Benefit), Total $ 58.2 $ 26.4 $ 12.0
Tax Jurisdiction of Domicile [Extensible Enumeration] UNITED STATES    
Percent      
Income tax expense at the U.S. federal statutory rate 21.00% 21.00% 21.00%
FCPA settlement   26.70%  
State income taxes, net of federal benefit 3.90% 10.10% 5.00%
Non-deductible compensation   7.10% 4.40%
Foreign tax effects    
Nontaxable or nondeductible items:      
Bargain purchase gain (2.50%)    
Compensation 1.10%    
Other 0.80%    
Tax benefit from stock-based compensation (0.60%) (1.70%) (5.10%)
Other     (8.60%)
Pension settlement   4.70% 3.90%
Effective income tax rate 23.70% 67.90% 20.60%