Summary of Significant Accounting Policies Inventories (Details) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2020	Jul. 31, 2019
Accounting Policies [Abstract]
Finished products	$ 85,547	$ 77,532
Work-in-process	24,044	20,515
Raw materials and supplies	26,071	21,990
Inventories	$ 135,662	$ 120,037
Percentage of LIFO Inventory	14.70%	13.40%
Inventory, LIFO Reserve, Effect on Income, Net	$ 7,195	$ 7,259

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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The difference between the change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods and any LIFO decrement which have been reflected in the statement of income during the period.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

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