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Inventories - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
	Mar. 31, 2022	Mar. 31, 2022	Sep. 30, 2021
Inventory [Line Items]
Slow moving and obsolete inventory reserve	$ 6,828,000	$ 6,828,000	$ 5,397,000
Three to Four Years Old Inventory [Member]
Inventory [Line Items]
Cost basis reduction in inventory, percentage		50.00%
Inventory, minimum time period on the shelf, years	3 years
Inventory, maximum time period on the shelf, years	4 years
Four to Five Years Old Inventory [Member]
Inventory [Line Items]
Cost basis reduction in inventory, percentage		75.00%
Inventory, minimum time period on the shelf, years		4 years
Inventory, maximum time period on the shelf, years		5 years
Greater Than Five Years Old Inventory [Member]
Inventory [Line Items]
Inventory, minimum time period on the shelf, years		5 years
Inventory valuation estimate		$ 0

X

- Definition

Represents the percentage cost basis reduction for inventories related to obsolescence, excessive levels, deterioration, possible alternative uses and other factors in determining net realizable value. Inventories are valued at the lower of cost or market, with cost being determined principally by using the last-in, first-out (LIFO) method and market defined as replacement cost for raw materials and net realizable value for work in process and finished goods. Appropriate consideration is given to obsolescence, excessive levels, deterioration, possible alternative uses and other factors in determining net realizable value. The cost of work in process and finished goods includes materials, direct labor, variable costs and overhead. The Company evaluates the need to record inventory adjustments on all inventories, including raw material, work in process, finished goods, spare parts and used equipment. Used equipment acquired by the Company on trade-in from customers is carried at estimate

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Inventory cost basis determination period maximum.

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- Definition

Represents the inventory valuation estimate amount after accounting for inventories related to obsolescence, excessive levels, deterioration, possible alternative uses and other factors in determining net realizable value. Inventories are valued at the lower of cost or market, with cost being determined principally by using the last-in, first-out (LIFO) method and market defined as replacement cost for raw materials and net realizable value for work in process and finished goods. Appropriate consideration is given to obsolescence, excessive levels, deterioration, possible alternative uses and other factors in determining net realizable value. The cost of work in process and finished goods includes materials, direct labor, variable costs and overhead. The Company evaluates the need to record inventory adjustments on all inventories, including raw material, work in process, finished goods, spare parts and used equipment. Used equipment acquired by the Company on trade-in from customers i

+ References

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- Definition

Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(c))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

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