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v3.25.1

Description of Business and Basis of Presentation - Narrative (Details) $ / shares in Units, $ in Millions |  |  | 6 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jan. 06, 2025 numberOfEmployee | Jan. 03, 2025 numberOfEmployee | Mar. 31, 2025 a Segment classification $ / shares | Mar. 25, 2025 USD ($) $ / shares | Sep. 30, 2024 $ / shares
Property Plant And Equipment [Line Items] |  |  |  |  |
Area of land sold |  |  | 51,300 |  |
Area of mineral rights |  |  | 46,900 |  |
Number of business segments | Segment |  |  | 2 |  |
Restructuring and related cost, expected number of positions eliminated | numberOfEmployee | 135 | 172 |  |  |
Share repurchase program, authorized, amount | $ |  |  |  | $ 50.0 |
Common stock, par value per share (in dollars per share) | $ / shares |  |  | $ 1.00 | $ 1.00 | $ 1.00
Land |  |  |  |  |
Property Plant And Equipment [Line Items] |  |  |  |  |
Number of primary classifications | classification |  |  | 2 |  |

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- Definition Area Of Mineral Rights + References No definition available. + Details
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- Definition Property, Plant and Equipment, Number of Classifications + References No definition available. + Details
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- Definition Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 505 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481520/505-30-50-4 + Details
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- Definition Area of land held. + References No definition available. + Details
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- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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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 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-18 + Details
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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A + Details
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