v3.26.1
Financial Instruments (Tables)
6 Months Ended
Mar. 31, 2026
Financial Instruments, Owned, at Fair Value, by Type, Alternative [Abstract]  
Schedule of Long-Term Debt Based on these criteria, the fair market value of long-term debt, including current portion, was as follows (in thousands): 
 March 31, 2026September 30, 2025
 Carrying
Amount
Fair ValueCarrying
Amount
Fair Value
Long-Term Debt$2,384,882 $2,379,031 $2,682,861 $2,696,145 
Schedule of Other Investments The components of the Company's Other Investments are as follows (in thousands):
At March 31, 2026At September 30, 2025
Life Insurance Contracts$41,772 $44,478 
Equity Mutual Fund13,872 13,786 
Fixed Income Mutual Fund10,226 10,082 
$65,870 $68,346 
Schedule of Cash Flow Hedges
The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the
Three Months Ended March 31, 2026 and 2025 (Thousands of Dollars)
Derivatives in Cash Flow Hedging RelationshipsAmount of Derivative Gain or (Loss) Recognized in Other Comprehensive Income (Loss) on
the Consolidated Statement of
Comprehensive Income (Loss)
for the
 Three Months Ended
 March 31,
Location of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of IncomeAmount of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income for the
 Three Months Ended
 March 31,
 20262025 20262025
Commodity Contracts$(1,739)$(208,829)Operating Revenue$(48,694)$(7,834)
Foreign Currency Contracts(451)(217)Operating Revenue(66)(326)
Total$(2,190)$(209,046) $(48,760)$(8,160)

The Effect of Derivative Financial Instruments on the Statement of Financial Performance for the
Six Months Ended March 31, 2026 and 2025 (Thousands of Dollars)
Derivatives in Cash Flow Hedging Relationships Amount of Derivative Gain or
(Loss) Recognized in Other
Comprehensive Income (Loss) on
the Consolidated Statement of
Comprehensive Income (Loss)
for the
 Six Months Ended
March 31,
Location of Derivative Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheet into the Consolidated Statement of Income Amount of Derivative Gain or
(Loss) Reclassified from
Accumulated Other
Comprehensive Income (Loss) on
the Consolidated Balance Sheet
into the Consolidated Statement of
Income for the
 Six Months Ended
 March 31,
 20262025 20262025
Commodity Contracts$47,141 $(260,738)Operating Revenue$(35,299)$21,894 
Foreign Currency Contracts(233)(1,824)Operating Revenue(186)(550)
Total$46,908 $(262,562) $(35,485)$21,344