Details of Selected Balance Sheet Accounts - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Details of Selected Balance Sheet Accounts [Abstract]
Finished goods and purchased products	$ 107,691	$ 96,195
Work in process	21,963	20,552
Raw materials	110,719	111,197
Total inventories	240,373	227,944
Allowance for excess or obsolete inventory	(19,031)	(18,551)
Inventories, net	$ 221,342	$ 209,393

Details of Selected Balance Sheet Accounts [Abstract]

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Other inventory finished goods and purchased products.

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

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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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