v3.26.1
Restricted Investments - Debt Securities (Details) - USD ($)
$ in Thousands
Jun. 30, 2026
Sep. 30, 2025
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost $ 10,907 $ 23,030
Gross Unrealized Gains 42 265
Gross Unrealized Losses 79 119
Fair Value 10,870 23,176
U.S. government securities    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 6,229 13,938
Gross Unrealized Gains 5 96
Gross Unrealized Losses 64 63
Fair Value 6,170 13,971
Corporate debt securities    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 3,099 5,552
Gross Unrealized Gains 31 138
Gross Unrealized Losses 8 19
Fair Value 3,122 5,671
Municipal government securities    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost   1,170
Gross Unrealized Gains   8
Gross Unrealized Losses   21
Fair Value   1,157
Other debt securities    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 1,579 2,370
Gross Unrealized Gains 6 23
Gross Unrealized Losses 7 16
Fair Value $ 1,578 $ 2,377