Inventories (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Inventories
Raw material and common parts	$ 15,239,000	$ 14,534,000
Work-in-process	3,490,000	3,258,000
Finished goods	2,361,000	2,510,000
Inventory, Gross	21,090,000	20,302,000
Less inventory reserve	(1,083,000)	(1,258,000)
Total inventories	$ 20,007,000	$ 19,044,000

No definition available.

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount of valuation reserve for inventory.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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