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Benefit Plans Components of Benefit Plans (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Defined Benefit Plan Disclosure |  |  |
Fixed and variable fund annual maximum contribution | $ 10,000 |  |
Defined contribution plan contribution amount | $ 105,000,000 | $ 97,000,000 | $ 92,000,000
Minimum |  |  |
Defined Benefit Plan Disclosure |  |  |
Threshold for Deferral of Actuarial Gain/Loss Under Corridor Approach | 10.00% |  |

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- Definition The maximum annual contribution that employees can make to the fixed and variable fund benefit. The fixed fund benefit is a benefit that earns a specified rate of interest on contributions made by employees. The variable fund is a benefit that invests employee contributions in the Spartan U.S. Equity Index Fund-Fidelity Advantage Class (Spartan). + References No definition available. + Details
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- Definition Threshold for Deferral of Actuarial Gain/Loss Under Corridor Approach + References No definition available. + 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 No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 70 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480794/715-70-50-1 + Details
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- Details
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