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v3.23.2

Retirement Benefits (Schedule Of Net Benefit Costs) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
DB Pension Plans |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | $ 8 | $ 11 | $ 15 | $ 23
Interest cost | 26 | 20 | 53 | 38
Expected return on plan assets | (55) | (52) | (110) | (104)
Amortization of |  |  |  |
Net loss | 3 | 10 | 6 | 27
Prior service cost (credit) | 1 | 1 | 2 | 2
Settlement loss | 3 | 2 | 5 | 4
Net periodic credit | (14) | (8) | (29) | (10)
DB Pension Plans | Volatility Mechanism |  |  |  |
Amortization of |  |  |  |
Deferred costs (credits) |  |  | 6 |
DB Pension Plans | Consumers Energy Company |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | 7 | 11 | 14 | 23
Interest cost | 26 | 20 | 51 | 36
Expected return on plan assets | (52) | (50) | (104) | (99)
Amortization of |  |  |  |
Net loss | 2 | 9 | 5 | 25
Prior service cost (credit) | 1 | 1 | 2 | 2
Settlement loss | 3 | 2 | 5 | 4
Net periodic credit | (13) | (7) | (27) | (9)
OPEB Plan |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | 3 | 5 | 6 | 9
Interest cost | 11 | 7 | 22 | 14
Expected return on plan assets | (25) | (29) | (51) | (58)
Amortization of |  |  |  |
Net loss | 3 | 1 | 6 | 1
Prior service cost (credit) | (11) | (14) | (21) | (26)
Settlement loss | 0 | 0 | 0 | 0
Net periodic credit | (19) | (30) | (38) | (60)
OPEB Plan | Volatility Mechanism |  |  |  |
Amortization of |  |  |  |
Deferred costs (credits) |  |  | (12) |
OPEB Plan | Consumers Energy Company |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | 3 | 5 | 6 | 9
Interest cost | 10 | 7 | 21 | 14
Expected return on plan assets | (24) | (27) | (48) | (54)
Amortization of |  |  |  |
Net loss | 3 | 0 | 6 | 0
Prior service cost (credit) | (10) | (13) | (20) | (25)
Settlement loss | 0 | 0 | 0 | 0
Net periodic credit | $ (18) | $ (28) | $ (35) | $ (56)

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