v3.26.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, RELATED RISKS AND UNCERTAINTIES - Narrative (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Sep. 30, 2025
Sep. 30, 2024
Summary Of Significant Accounting Policies [Line Items]            
Restricted cash $ 34.9   $ 34.9   $ 29.1  
Additional cash and cash equivalents restricted at the election of management for potential insurance claims 33.6   33.6   $ 27.4  
Premium revenues and expenses 17.3 $ 16.3 55.2 $ 50.8    
Underwriting expense (3.7) 29.3 (1.6) 43.5    
Casualty insurance premiums 12.6 10.1 35.9 31.8    
Stop-loss medical expenses $ 4.8 $ 4.4 $ 11.5 $ 14.8    
International Locations | Geographic Concentration Risk | Operating Revenue            
Summary Of Significant Accounting Policies [Line Items]            
Concentration percentage 42.70% 36.70% 41.70% 31.40%    
International Locations | Geographic Concentration Risk | Operating Revenue | Middle East            
Summary Of Significant Accounting Policies [Line Items]            
Concentration percentage 15.70% 16.10% 16.20% 13.20%    
International Locations | Geographic Concentration Risk | Operating Revenue | Saudi Arabia            
Summary Of Significant Accounting Policies [Line Items]            
Concentration percentage 7.20% 10.00% 6.90% 7.40%    
KCA Deutag Acquisition            
Summary Of Significant Accounting Policies [Line Items]            
Restricted cash           $ 1,200.0