Retirement Benefits

9 Months Ended

Sep. 30, 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						Nine Months Ended						Three Months Ended						Nine Months Ended
September 30	2021			2020			2021			2020			2021			2020			2021			2020
CMS Energy, including Consumers
Net periodic cost (credit)
Service cost		$	14		$	12		$	41		$	37		$	5		$	4		$	14		$	12
Interest cost		14			20			44			61			6			8			17			25
Settlement loss		—			1			—			1			—			—			—			—
Expected return on plan assets		(51)			(47)			(155)			(143)			(28)			(25)			(82)			(75)
Amortization of:
Net loss		25			23			76			67			2			4			6			11
Prior service cost (credit)		1			—			3			1			(14)			(14)			(40)			(42)
Settlement loss		1			—			4			—			—			—			—			—
Net periodic cost (credit)		$	4		$	9		$	13		$	24		$	(29)		$	(23)		$	(85)		$	(69)
Consumers
Net periodic cost (credit)
Service cost		$	14		$	12		$	40		$	36		$	4		$	3		$	13		$	11
Interest cost		14			20			42			59			6			8			17			24
Expected return on plan assets		(49)			(45)			(147)			(136)			(26)			(23)			(77)			(70)
Amortization of:
Net loss		24			22			73			64			2			4			6			11
Prior service cost (credit)		1			—			3			1			(12)			(13)			(38)			(40)
Settlement loss		1			—			4			—			—			—			—			—
Net periodic cost (credit)		$	5		$	9		$	15		$	24		$	(26)		$	(21)		$	(79)		$	(64)

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						Nine Months Ended						Three Months Ended						Nine Months Ended
September 30	2021			2020			2021			2020			2021			2020			2021			2020
CMS Energy, including Consumers
Net periodic cost (credit)
Service cost		$	14		$	12		$	41		$	37		$	5		$	4		$	14		$	12
Interest cost		14			20			44			61			6			8			17			25
Settlement loss		—			1			—			1			—			—			—			—
Expected return on plan assets		(51)			(47)			(155)			(143)			(28)			(25)			(82)			(75)
Amortization of:
Net loss		25			23			76			67			2			4			6			11
Prior service cost (credit)		1			—			3			1			(14)			(14)			(40)			(42)
Settlement loss		1			—			4			—			—			—			—			—
Net periodic cost (credit)		$	4		$	9		$	13		$	24		$	(29)		$	(23)		$	(85)		$	(69)
Consumers
Net periodic cost (credit)
Service cost		$	14		$	12		$	40		$	36		$	4		$	3		$	13		$	11
Interest cost		14			20			42			59			6			8			17			24
Expected return on plan assets		(49)			(45)			(147)			(136)			(26)			(23)			(77)			(70)
Amortization of:
Net loss		24			22			73			64			2			4			6			11
Prior service cost (credit)		1			—			3			1			(12)			(13)			(38)			(40)
Settlement loss		1			—			4			—			—			—			—			—
Net periodic cost (credit)		$	5		$	9		$	15		$	24		$	(26)		$	(21)		$	(79)		$	(64)