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Retirement Benefits | 3 Months Ended
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Mar. 31, 2017
Retirement Benefits | 8:Retirement Benefits CMS Energy and Consumers provide pension, OPEB, and other retirement benefits to employees under a number of different plans. CMS Energy and Consumers elected to adopt ASU 2017‑07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, as of January 1, 2017. For further details on the implementation of this standard, see Note 1, New Accounting Standards. 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 Plan |  | OPEB Plan |
﻿Three Months Ended March 31 | 2017 | 2016 |  | 2017 | 2016 |
﻿CMS Energy, including Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 11 |  | $ | 11 |  |  | $ | 5 |  | $ | 5 |
﻿Interest cost |  |  | 22 |  |  | 21 |  |  |  | 13 |  |  | 12 |
﻿Expected return on plan assets |  |  | (38) |  |  | (37) |  |  |  | (22) |  |  | (22) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 20 |  |  | 17 |  |  |  | 8 |  |  | 5 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (9) |  |  | (10) |
﻿Net periodic cost (credit) |  | $ | 16 |  | $ | 13 |  |  | $ | (5) |  | $ | (10) |
﻿Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 11 |  | $ | 10 |  |  | $ | 5 |  | $ | 4 |
﻿Interest cost |  |  | 21 |  |  | 21 |  |  |  | 13 |  |  | 11 |
﻿Expected return on plan assets |  |  | (37) |  |  | (36) |  |  |  | (21) |  |  | (20) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 20 |  |  | 17 |  |  |  | 8 |  |  | 6 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (9) |  |  | (10) |
﻿Net periodic cost (credit) |  | $ | 16 |  | $ | 13 |  |  | $ | (4) |  | $ | (9) |
﻿
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. CMS Energy and Consumers elected to adopt ASU 2017‑07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, as of January 1, 2017. For further details on the implementation of this standard, see Note 1, New Accounting Standards. 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 Plan |  | OPEB Plan |
﻿Three Months Ended March 31 | 2017 | 2016 |  | 2017 | 2016 |
﻿CMS Energy, including Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 11 |  | $ | 11 |  |  | $ | 5 |  | $ | 5 |
﻿Interest cost |  |  | 22 |  |  | 21 |  |  |  | 13 |  |  | 12 |
﻿Expected return on plan assets |  |  | (38) |  |  | (37) |  |  |  | (22) |  |  | (22) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 20 |  |  | 17 |  |  |  | 8 |  |  | 5 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (9) |  |  | (10) |
﻿Net periodic cost (credit) |  | $ | 16 |  | $ | 13 |  |  | $ | (5) |  | $ | (10) |
﻿Consumers
﻿Net periodic cost (credit)
﻿Service cost |  | $ | 11 |  | $ | 10 |  |  | $ | 5 |  | $ | 4 |
﻿Interest cost |  |  | 21 |  |  | 21 |  |  |  | 13 |  |  | 11 |
﻿Expected return on plan assets |  |  | (37) |  |  | (36) |  |  |  | (21) |  |  | (20) |
﻿Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |
﻿Net loss |  |  | 20 |  |  | 17 |  |  |  | 8 |  |  | 6 |
﻿Prior service cost (credit) |  |  | 1 |  |  | 1 |  |  |  | (9) |  |  | (10) |
﻿Net periodic cost (credit) |  | $ | 16 |  | $ | 13 |  |  | $ | (4) |  | $ | (9) |
﻿

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