Retirement Benefits (Tables)

3 Months Ended

Mar. 31, 2021

Defined Benefit Plan Disclosure [Line Items]

Schedule Of Net Benefit 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]

Schedule Of Net Benefit 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)