Amount Retained By Group Captive Insurance Per Claim Paid

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- Definition

Amount Retained Per Claim Paid

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No definition available.

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- Definition

Capitalized Costs, Pre-production Stripping Costs

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- Definition

Stop-Loss Insurance Purchased To Limit Claim Claim Loss

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- Definition

Summary Of Accounting Policies [Line Items]

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 275
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
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-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-18

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- Definition

Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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- Definition

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483489/210-10-50-1

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 49
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-49

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
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-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-18

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

No definition available.

+ Details

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- Definition

Amount of capitalized production cost incurred during period for oil- and gas-producing activities. Includes cost incurred to operate and maintain well and related equipment and facility.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 932
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10(a)(20))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479664/932-10-S99-1

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- Definition

Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482913/230-10-50-8

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- Definition

This element represents the noncurrent portion of investments which are not defined as or included in marketable (debt, equity, or other) securities that are pledged or subject to withdrawal restrictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477220/954-210-45-4

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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478600/954-210-50-2

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- Definition

The amount of weighted average cost inventory present at the reporting date when inventory is valued using different valuation methods.

+ References

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Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Sep. 30, 2025 USD ($) segment	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Oct. 01, 2021 USD ($)
Summary Of Accounting Policies [Line Items]
Restricted cash	$ 2,953,000	$ 1,998,000
Restricted investments	23,176,000	18,020,000
Debt securities, available-for-sale, allowance for credit loss	0	0	$ 0
Weighted average cost inventory amount	136,500,000	95,800,000
FIFO inventory amount	$ 18,600,000	10,900,000
Number of operating segments \| segment	1
Number of reporting units \| segment	1
Amount retained for each claim paid				$ 1,000,000
Amount retained by CIRCA per claim paid				$ 550,000
Capitalized costs, pre-production stripping costs	$ 1,700,000	1,700,000
Production costs, period cost	$ 3,700,000	$ 3,200,000	$ 3,100,000
Departments of Transportation \| Revenues \| Customer Concentration Risk
Summary Of Accounting Policies [Line Items]
Concentration risk percentage	43.40%	40.70%	36.20%
Minimum
Summary Of Accounting Policies [Line Items]
Stop-loss insurance purchased	$ 100,000
Maximum
Summary Of Accounting Policies [Line Items]
Stop-loss insurance purchased	$ 225,000