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Retirement Benefits | 3 Months Ended
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Mar. 31, 2018
Retirement Benefits | 8: Retirement Benefits CMS Energy and Consumers provide pension, OPEB, and other retirement benefits to employees under a number of different plans. In November 2017, CMS Energy and Consumers approved certain amendments to the OPEB Plan, resulting in higher OPEB Plan credits in 2018 compared to 2017. Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefits plans:
﻿ |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿In Millions
﻿ | DB Pension Plans |  | OPEB Plan |
﻿Three Months Ended March 31 | 2018 | 2017 |  | 2018 | 2017 |
﻿CMS Energy, including Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 12 |  | $ | 11 |  |  | $ | 4 |  | $ | 5 |
﻿Interest cost |  |  | 22 |  |  | 22 |  |  |  | 9 |  |  | 13 |
﻿Expected return on plan assets |  |  | (37) |  |  | (38) |  |  |  | (24) |  |  | (22) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 18 |  |  | 20 |  |  |  | 4 |  |  | 8 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (17) |  |  | (9) |
﻿Net periodic cost (credit) |  | $ | 16 |  | $ | 16 |  |  | $ | (24) |  | $ | (5) |
﻿Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 12 |  | $ | 11 |  |  | $ | 4 |  | $ | 5 |
﻿Interest cost |  |  | 21 |  |  | 21 |  |  |  | 8 |  |  | 13 |
﻿Expected return on plan assets |  |  | (35) |  |  | (37) |  |  |  | (23) |  |  | (21) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 18 |  |  | 20 |  |  |  | 4 |  |  | 8 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (16) |  |  | (9) |
﻿Net periodic cost (credit) |  | $ | 17 |  | $ | 16 |  |  | $ | (23) |  | $ | (4) |
﻿
Consumers Energy Company [Member] |
Retirement Benefits | 8: Retirement Benefits CMS Energy and Consumers provide pension, OPEB, and other retirement benefits to employees under a number of different plans. In November 2017, CMS Energy and Consumers approved certain amendments to the OPEB Plan, resulting in higher OPEB Plan credits in 2018 compared to 2017. Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefits plans:
﻿ |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿ |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿In Millions
﻿ | DB Pension Plans |  | OPEB Plan |
﻿Three Months Ended March 31 | 2018 | 2017 |  | 2018 | 2017 |
﻿CMS Energy, including Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 12 |  | $ | 11 |  |  | $ | 4 |  | $ | 5 |
﻿Interest cost |  |  | 22 |  |  | 22 |  |  |  | 9 |  |  | 13 |
﻿Expected return on plan assets |  |  | (37) |  |  | (38) |  |  |  | (24) |  |  | (22) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 18 |  |  | 20 |  |  |  | 4 |  |  | 8 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (17) |  |  | (9) |
﻿Net periodic cost (credit) |  | $ | 16 |  | $ | 16 |  |  | $ | (24) |  | $ | (5) |
﻿Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 12 |  | $ | 11 |  |  | $ | 4 |  | $ | 5 |
﻿Interest cost |  |  | 21 |  |  | 21 |  |  |  | 8 |  |  | 13 |
﻿Expected return on plan assets |  |  | (35) |  |  | (37) |  |  |  | (23) |  |  | (21) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 18 |  |  | 20 |  |  |  | 4 |  |  | 8 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (16) |  |  | (9) |
﻿Net periodic cost (credit) |  | $ | 17 |  | $ | 16 |  |  | $ | (23) |  | $ | (4) |
﻿

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- Definition The entire disclosure for pension and other postretirement benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -URI http://asc.fasb.org/topic&trid=2235017 + Details
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- Details
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