Cash And Cash Equivalents (Schedule Of Cash And Cash Equivalents, Including Restricted Amounts) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 452	$ 32
Restricted cash and cash equivalents	24	17
Cash and cash equivalents, including restricted amounts	476	185	$ 157	$ 175
Discontinued Operations, Held-for-sale
Cash and Cash Equivalents [Line Items]
Current assets held for sale	0	136
Consumers Energy Company
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	22	20
Restricted cash and cash equivalents	22	15
Cash and cash equivalents, including restricted amounts	$ 44	$ 35	$ 28	$ 56