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v3.22.2.2

Retirement Benefits (Schedule Of Net Benefit Costs) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
DB Pension Plans |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | $ 9 | $ 14 | $ 32 | $ 41
Interest cost | 21 | 14 | 59 | 44
Expected return on plan assets | (51) | (51) | (155) | (155)
Amortization of |  |  |  |
Net loss | 5 | 25 | 32 | 76
Prior service cost (credit) | 1 | 1 | 3 | 3
Settlement loss | 2 | 1 | 6 | 4
Net periodic cost (credit) | (13) | 4 | (23) | 13
DB Pension Plans | Consumers Energy Company |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | 9 | 14 | 32 | 40
Interest cost | 20 | 14 | 56 | 42
Expected return on plan assets | (48) | (49) | (147) | (147)
Amortization of |  |  |  |
Net loss | 5 | 24 | 30 | 73
Prior service cost (credit) | 1 | 1 | 3 | 3
Settlement loss | 2 | 1 | 6 | 4
Net periodic cost (credit) | (11) | 5 | (20) | 15
OPEB Plan |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | 4 | 5 | 13 | 14
Interest cost | 7 | 6 | 21 | 17
Expected return on plan assets | (29) | (28) | (87) | (82)
Amortization of |  |  |  |
Net loss | 0 | 2 | 1 | 6
Prior service cost (credit) | (12) | (14) | (38) | (40)
Settlement loss | 0 | 0 | 0 | 0
Net periodic cost (credit) | (30) | (29) | (90) | (85)
OPEB Plan | Consumers Energy Company |  |  |  |
Defined Benefit Plan, Roll Forwards [Abstract] |  |  |  |
Service cost | 4 | 4 | 13 | 13
Interest cost | 6 | 6 | 20 | 17
Expected return on plan assets | (26) | (26) | (80) | (77)
Amortization of |  |  |  |
Net loss | 0 | 2 | 0 | 6
Prior service cost (credit) | (13) | (12) | (38) | (38)
Settlement loss | 0 | 0 | 0 | 0
Net periodic cost (credit) | $ (29) | $ (26) | $ (85) | $ (79)

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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 + Details
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