Retirement Benefits

3 Months Ended

Mar. 31, 2021

Defined Benefit Plan Disclosure [Line Items]

Retirement Benefits

Retirement BenefitsCMS Energy and Consumers provide pension, OPEB, and other retirement benefits to employees under a number of different plans.

Costs: 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	2021			2020			2021			2020
CMS Energy, including Consumers
Net periodic cost (credit)
Service cost		$	14		$	12		$	4		$	4
Interest cost		15			21			6			8
Expected return on plan assets		(52)			(48)			(27)			(25)
Amortization of:
Net loss		25			22			2			4
Prior service cost (credit)		1			—			(13)			(14)
Settlement loss		1			—			—			—
Net periodic cost (credit)		$	4		$	7		$	(28)		$	(23)
Consumers
Net periodic cost (credit)
Service cost		$	13		$	12		$	4		$	4
Interest cost		14			20			6			8
Expected return on plan assets		(49)			(45)			(25)			(23)
Amortization of:
Net loss		25			21			2			4
Prior service cost (credit)		1			—			(13)			(14)
Settlement loss		1			—			—			—
Net periodic cost (credit)		$	5		$	8		$	(26)		$	(21)

Consumers Energy Company

Defined Benefit Plan Disclosure [Line Items]

Retirement Benefits

Retirement BenefitsCMS Energy and Consumers provide pension, OPEB, and other retirement benefits to employees under a number of different plans.

Costs: 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	2021			2020			2021			2020
CMS Energy, including Consumers
Net periodic cost (credit)
Service cost		$	14		$	12		$	4		$	4
Interest cost		15			21			6			8
Expected return on plan assets		(52)			(48)			(27)			(25)
Amortization of:
Net loss		25			22			2			4
Prior service cost (credit)		1			—			(13)			(14)
Settlement loss		1			—			—			—
Net periodic cost (credit)		$	4		$	7		$	(28)		$	(23)
Consumers
Net periodic cost (credit)
Service cost		$	13		$	12		$	4		$	4
Interest cost		14			20			6			8
Expected return on plan assets		(49)			(45)			(25)			(23)
Amortization of:
Net loss		25			21			2			4
Prior service cost (credit)		1			—			(13)			(14)
Settlement loss		1			—			—			—
Net periodic cost (credit)		$	5		$	8		$	(26)		$	(21)