RETIREMENT PLANS - ASSET CATERGORY ALLOCATION (Details)	Sep. 30, 2025	Sep. 30, 2024
Cash and cash equivalents
Entity's year-end target allocation, by asset category, and the actual asset allocations
Actual asset allocation	1.00%	4.00%
Fixed income securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Actual asset allocation	15.00%	19.00%
Equity securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Actual asset allocation	80.00%	73.00%
Other investment
Entity's year-end target allocation, by asset category, and the actual asset allocations
Actual asset allocation	4.00%	4.00%
Minimum | Cash and cash equivalents
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	0.00%
Minimum | Fixed income securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	15.00%
Minimum | Equity securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	45.00%
Minimum | Other investment
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	0.00%
Maximum | Cash and cash equivalents
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	25.00%
Maximum | Fixed income securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	40.00%
Maximum | Equity securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	75.00%
Maximum | Other investment
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	10.00%