Property, Plant and Equipment (Details) $ in Thousands	Sep. 30, 2019 USD ($) item	Sep. 30, 2018 USD ($)
Property, plant and equipment
Gross amount	$ 351,244	$ 343,410
Less accumulated depreciation	(181,278)	(164,010)
Net amount	169,966	179,400
Shanghai
Property, plant and equipment
Assets under a capital lease	135	200
La Porte
Property, plant and equipment
Assets under a capital lease	$ 7,070	7,483
Number of leased buildings \| item	2
Land and land improvements
Property, plant and equipment
Gross amount	$ 9,446	9,462
Buildings and improvements
Property, plant and equipment
Gross amount	45,486	45,327
Machinery and equipment
Property, plant and equipment
Gross amount	293,542	281,329
Construction in process
Property, plant and equipment
Gross amount	$ 2,770	$ 7,292

Represents the number of leased buildings.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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