Inventories (Schedule of Inventories) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Sep. 30, 2017
Inventories
Raw Materials	$ 60,355	$ 59,034
Work in progress	106,065	103,790
Component Parts	285,674	262,755
Finished Goods	51,429	47,926
Inventory, net	$ 503,523	$ 473,505

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
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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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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.

+ References

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-Publisher FASB
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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

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of component parts, which includes items that can be sold separately as finished goods or included in the manufacture of other products.

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