Supplementary Financial Statement Information Inventory (Policies)	12 Months Ended
	Sep. 30, 2020
Inventory Disclosure [Abstract]
Inventory, Policy [Policy Text Block]	InventoriesInventories are valued at lower of cost or market. Inventory costs are determined by the last-in, first-out (“LIFO”) method for approximately 16% and 30% of our inventories as of September 30, 2020 and September 30, 2019. Costs for other inventories have been determined principally by the first-in, first-out (“FIFO”) method. If the FIFO method of inventory accounting had been used for all inventories, they would have been approximately $5.5 million and $0.3 million higher than reported as of September 30, 2020 and September 30, 2019.