Regulatory Matters	3 Months Ended
Regulatory Matters	Mar. 31, 2021
Public Utilities, General Disclosures [Line Items]
Regulatory Matters	Regulatory Matters Regulatory matters are critical to Consumers. The Michigan Attorney General, ABATE, the MPSC Staff, and certain other parties typically participate in MPSC proceedings concerning Consumers, such as Consumers’ rate cases and PSCR and GCR processes. These parties often challenge various aspects of those proceedings, including the prudence of Consumers’ policies and practices, and seek cost disallowances and other relief. The parties also have appealed significant MPSC orders. Depending upon the specific issues, the outcomes of rate cases and proceedings, including judicial proceedings challenging MPSC orders or other actions, could negatively affect CMS Energy’s and Consumers’ liquidity, financial condition, and results of operations. Consumers cannot predict the outcome of these proceedings. There are multiple appeals pending that involve various issues concerning cost recovery from customers, the adequacy of the record of evidence supporting the recovery of Smart Energy investments, and other matters. Consumers is unable to predict the outcome of these appeals. Reserve for Customer Refunds: In December 2020, the MPSC issued an order authorizing Consumers to refund $28 million voluntarily to utility customers. In February 2021, Consumers submitted a filing proposing that the refund take the form of incremental spending in 2021 above amounts included in rates on various programs, including electric service restoration and gas and electric technology expenses. Consumers’ proposal indicates that if it does not achieve the incremental spending, the remaining balance would be provided to electric or gas utility customers through a bill credit. Consumers had recorded a current regulatory liability of $28 million at March 31, 2021 and December 31, 2020 related to this voluntary refund. Voluntary Transmission Asset Sale Gain Share: In October 2020, Consumers completed a sale of the electric utility’s remaining transmission equipment to METC. In December 2020, Consumers filed an application with the MPSC requesting approval to share voluntarily half of the gain from the sale with electric utility customers; this application was approved by the MPSC in February 2021. Consumers will share the gain through incremental service restoration spending in 2021 above amounts included in rates or through a bill credit to electric utility customers in 2022. As a result, the $14 million gain to be shared with customers was recorded on Consumers’ consolidated balance sheets as a current regulatory liability at March 31, 2021 and December 31, 2020. Energy Waste Reduction Plan Incentive: Consumers will file its 2020 energy waste reduction reconciliation in 2021, requesting the MPSC’s approval to collect from customers the maximum performance incentive of $42 million for exceeding statutory savings targets in 2020. Consumers recognized incentive revenue under this program of $42 million in 2020.
Consumers Energy Company
Public Utilities, General Disclosures [Line Items]
Regulatory Matters	Regulatory Matters Regulatory matters are critical to Consumers. The Michigan Attorney General, ABATE, the MPSC Staff, and certain other parties typically participate in MPSC proceedings concerning Consumers, such as Consumers’ rate cases and PSCR and GCR processes. These parties often challenge various aspects of those proceedings, including the prudence of Consumers’ policies and practices, and seek cost disallowances and other relief. The parties also have appealed significant MPSC orders. Depending upon the specific issues, the outcomes of rate cases and proceedings, including judicial proceedings challenging MPSC orders or other actions, could negatively affect CMS Energy’s and Consumers’ liquidity, financial condition, and results of operations. Consumers cannot predict the outcome of these proceedings. There are multiple appeals pending that involve various issues concerning cost recovery from customers, the adequacy of the record of evidence supporting the recovery of Smart Energy investments, and other matters. Consumers is unable to predict the outcome of these appeals. Reserve for Customer Refunds: In December 2020, the MPSC issued an order authorizing Consumers to refund $28 million voluntarily to utility customers. In February 2021, Consumers submitted a filing proposing that the refund take the form of incremental spending in 2021 above amounts included in rates on various programs, including electric service restoration and gas and electric technology expenses. Consumers’ proposal indicates that if it does not achieve the incremental spending, the remaining balance would be provided to electric or gas utility customers through a bill credit. Consumers had recorded a current regulatory liability of $28 million at March 31, 2021 and December 31, 2020 related to this voluntary refund. Voluntary Transmission Asset Sale Gain Share: In October 2020, Consumers completed a sale of the electric utility’s remaining transmission equipment to METC. In December 2020, Consumers filed an application with the MPSC requesting approval to share voluntarily half of the gain from the sale with electric utility customers; this application was approved by the MPSC in February 2021. Consumers will share the gain through incremental service restoration spending in 2021 above amounts included in rates or through a bill credit to electric utility customers in 2022. As a result, the $14 million gain to be shared with customers was recorded on Consumers’ consolidated balance sheets as a current regulatory liability at March 31, 2021 and December 31, 2020. Energy Waste Reduction Plan Incentive: Consumers will file its 2020 energy waste reduction reconciliation in 2021, requesting the MPSC’s approval to collect from customers the maximum performance incentive of $42 million for exceeding statutory savings targets in 2020. Consumers recognized incentive revenue under this program of $42 million in 2020.