Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash Flows from Operating Activities
Net income	$ 590	$ 514
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	767	729
Deferred income taxes and investment tax credits	140	89
Pension contributions	(531)	0
Other non-cash operating activities and reconciling adjustments	24	(11)
Cash provided by (used in) changes in assets and liabilities
Accounts and notes receivable and accrued revenue	218	297
Inventories	(34)	(49)
Accounts payable and accrued rate refunds	29	(82)
Other current and non-current assets and liabilities	(59)	(92)
Net cash provided by operating activities	1,144	1,395
Cash Flows from Investing Activities
Capital expenditures (excludes assets placed under finance lease)	(1,697)	(1,570)
Increase in EnerBank notes receivable	(480)	(328)
Purchase of notes receivable by EnerBank	(17)	(307)
Proceeds from sale of transmission equipment	0	96
Cost to retire property and other investing activities	(104)	(103)
Net cash used in investing activities	(2,298)	(2,212)
Cash Flows from Financing Activities
Proceeds from issuance of debt	2,353	2,076
Retirement of debt	(1,294)	(1,170)
Increase in EnerBank certificates of deposit	456	622
Decrease in notes payable	(90)	(97)
Issuance of common stock, net of issuance costs	107	9
Payment of dividends on common and preferred stock	(351)	(326)
Proceeds from the sale of membership interest in VIE to tax equity investor	417	0
Contribution from noncontrolling interest	31	0
Other financing costs	(74)	(39)
Net cash provided by financing activities	1,555	1,075
Net Increase in Cash and Cash Equivalents, Including Restricted Amounts	401	258
Cash and Cash Equivalents, Including Restricted Amounts, Beginning of Period	157	175
Cash and Cash Equivalents, Including Restricted Amounts, End of Period	558	433
Non-cash transactions
Capital expenditures not paid	140	135
Consumers Energy Company
Cash Flows from Operating Activities
Net income	625	537
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	753	716
Deferred income taxes and investment tax credits	136	37
Pension contributions	(518)	0
Other non-cash operating activities and reconciling adjustments	(21)	(24)
Cash provided by (used in) changes in assets and liabilities
Accounts and notes receivable and accrued revenue	190	230
Inventories	(34)	(52)
Accounts payable and accrued rate refunds	29	(76)
Other current and non-current assets and liabilities	(75)	(117)
Net cash provided by operating activities	1,085	1,251
Cash Flows from Investing Activities
Capital expenditures (excludes assets placed under finance lease)	(1,595)	(1,559)
Proceeds from sale of transmission equipment	0	76
Cost to retire property and other investing activities	(105)	(100)
Net cash used in investing activities	(1,700)	(1,583)
Cash Flows from Financing Activities
Proceeds from issuance of debt	1,528	918
Retirement of debt	(773)	(528)
Decrease in notes payable	(90)	(97)
Stockholder contribution	650	675
Payment of dividends on common and preferred stock	(450)	(397)
Other financing costs	(55)	(11)
Net cash provided by financing activities	810	560
Net Increase in Cash and Cash Equivalents, Including Restricted Amounts	195	228
Cash and Cash Equivalents, Including Restricted Amounts, Beginning of Period	28	56
Cash and Cash Equivalents, Including Restricted Amounts, End of Period	223	284
Non-cash transactions
Capital expenditures not paid	$ 156	$ 123