| Inventories (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Sep. 30, 2018 | 
|---|---|---|
| Inventories, net [Abstract] | ||
| Raw materials | $ 36,880 | $ 34,880 | 
| Work in process | 72,210 | 67,827 | 
| Finished goods | 78,563 | 77,744 | 
| Inventories | $ 187,653 | $ 180,451 | 
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- References 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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