Plant, Property, and Equipment (Summary of Average Capitalization Rates) (Details) - Consumers Energy Company	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Electric Utility
Property, Plant and Equipment [Line Items]
AFUDC capitalization rate	6.50%	6.20%	6.20%
Gas Utility
Property, Plant and Equipment [Line Items]
AFUDC capitalization rate	5.80%	5.60%	5.60%

Effective rate, including composite rate, of cost of financing additions to qualifying regulated assets, commonly called allowance for funds used during construction.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 980
-SubTopic 835
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481668/980-835-25-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 980
-SubTopic 835
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482064/980-835-45-1

Name:	us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration