Inventories (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Inventory [Line Items]
Raw materials	$ 10,379	$ 9,182
Work-in process	3,119	2,305
Finished products and components	2,146	2,221
Total	15,644	13,708
Domestic [Member]
Inventory [Line Items]
Raw materials	8,148	6,924
Work-in process	2,080	1,791
Finished products and components	1,216	1,366
Total	11,444	10,081
Foreign [Member]
Inventory [Line Items]
Raw materials	2,231	2,258
Work-in process	1,039	514
Finished products and components	930	855
Total	$ 4,200	$ 3,627

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-Subparagraph (SX 210.5-02(6)(a)(1))
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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/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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