Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Inventory.
Raw materials and supplies	$ 40,119	$ 42,851
Work-in-process	10,088	3,492
Finished goods	3,221	2,433
Total inventory	53,428	48,776
Inventory held at service locations	$ 5,700	$ 5,500

No definition available.

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- Definition

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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- Definition

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

+ References

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

Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. This amount is net of valuation reserves and adjustments.

+ References

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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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- Definition

Gross amount of inventory owned by the entity but in the hands of a customer, typically a reseller.

+ References

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