Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
Aug. 01, 2019	Sep. 30, 2019	Sep. 30, 2018
Property Plant And Equipment [Line Items]
Gain on disposal of property		$ 100	$ 27
Property, plant and equipment depreciation expense		$ 3,965	$ 4,040
Gessner Road, Houston, Texas [Member]
Property Plant And Equipment [Line Items]
Sale of real property for cash price	$ 8,300
Gain on disposal of property	$ 7,000

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 230
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-Section 45
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- Definition

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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