Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
Aug. 01, 2019	Sep. 30, 2020	Sep. 30, 2019
Property Plant And Equipment [Line Items]
Property held for sale		$ 587
Gain on disposal of property		116	$ 100
Property, plant and equipment depreciation expense		$ 4,016	$ 3,965
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

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Section 15
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-URI http://asc.fasb.org/extlink&oid=121558832&loc=d3e400-110220

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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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
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

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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
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-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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