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Retirement Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon |  | 2000.00% |  |
Defined Benefit Plan, Amortization of Gain (Loss) |  | $ (3.7) | $ (1.7) | $ (2.5)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 6.29% | 5.79% | 3.01%
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 100.00% |  |
Discount rate |  | 5.79% | 3.01% | 2.84%
Gain (loss) on corridor |  | 10.00% |  |
Defined Contribution Plan, Cost |  | $ 8.2 | $ 7.3 | $ 5.9
Equity Securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 30.00% |  |
Equity Securities [Member] | Minimum [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 27.00% |  |
Equity Securities [Member] | Maximum [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 33.00% |  |
Forecast [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Amortization of Gain (Loss) | $ (4.6) |  |  |

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- Definition Defined Benefit Plan, Expected Return on Plan Assets, Major Asset Classes, Time Horizon + References No definition available. + Details
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- Definition Defined Benefit Plan, Gain (Loss) On Corridor + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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