Retirement and Post-Retirement Employee Benefit Plans - Supplemental Plans’ Accumulated Benefit Obligation, Projected Benefit Obligation and Funded Status (Details) - Supplemental Executive Retirement Plans - USD ($) $ in Thousands |
12 Months Ended | ||
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Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2018 |
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Defined Benefit Plan Disclosure [Line Items] | |||
Accumulated benefit obligation | $ 122,207 | $ 138,772 | |
Change in projected benefit obligation: | |||
Benefit obligation at beginning of year | 143,987 | 121,370 | |
Service cost | 1,074 | 869 | $ 1,332 |
Interest cost | 4,188 | 5,127 | 4,988 |
Actuarial (gain) loss | 7,386 | 25,099 | |
Benefits paid | (4,766) | (8,478) | |
Settlements | (22,729) | 0 | |
Benefit obligation at end of year | 129,140 | 143,987 | 121,370 |
Change in plan assets: | |||
Fair value of plan assets at beginning of year | 0 | 0 | |
Employer contribution | 27,495 | 8,478 | |
Benefits paid | (4,766) | (8,478) | |
Settlements | (22,729) | 0 | |
Fair value of plan assets at end of year | 0 | 0 | $ 0 |
Reconciliation: | |||
Funded status | (129,140) | (143,987) | |
Unrecognized prior service cost | 0 | 0 | |
Unrecognized net loss | 0 | 0 | |
Net amount recognized | $ (129,140) | $ (143,987) |
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- Definition The amount of net actuarial (gain) loss that is not yet recognized in net periodic cost and that is recorded in regulatory asset. No definition available.
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- Definition The amount of unrecognized prior service cost that is not yet recognized in net periodic cost and that is recorded in regulatory asset. No definition available.
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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. No definition available.
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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Details
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