Inventories (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Inventory [Line Items]
Raw materials	$ 9,182	$ 7,482
Work-in process	2,305	1,608
Finished products and components	3,910	3,253
Total	15,397	12,343
Domestic [Member]
Inventory [Line Items]
Raw materials	6,924	5,731
Work-in process	1,791	1,324
Finished products and components	3,055	2,609
Total	11,770	9,664
Foreign [Member]
Inventory [Line Items]
Raw materials	2,258	1,751
Work-in process	514	284
Finished products and components	855	644
Total	$ 3,627	$ 2,679

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
-SubTopic 10
-Section S99
-Paragraph 1
-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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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