Inventories (Policies)	9 Months Ended
Jan. 31, 2020
Inventory Disclosure [Abstract]
Inventory, Policy [Policy Text Block]	Inventories are valued at the lower of cost or market. Some of our consolidated inventories are valued using the last-in, first-out (LIFO) method, which we use for the majority of our U.S. inventories.

Disclosure of inventory accounting policy for inventory classes, including, but not limited to, basis for determining inventory amounts, methods by which amounts are added and removed from inventory classes, loss recognition on impairment of inventories, and situations in which inventories are stated above cost.

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