v3.26.1
Fair Value of Financial Instruments (Details) - USD ($)
Jun. 30, 2026
Sep. 30, 2025
Recorded Amount    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-term debt $ 11,444,100,000 $ 7,543,000,000
Level 1 Inputs | Fair Value | Money Market    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 0 1,864,000,000
Level 2 Inputs | Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Long-term debt $ 11,163,500,000 $ 7,361,400,000