Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash Flows from Operating Activities
Net income	$ 243	$ 213
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	316	298
Deferred income taxes and investment tax credits	67	43
Pension contributions	(531)	0
Other non-cash operating activities and reconciling adjustments	9	16
Cash provided by (used in) changes in assets and liabilities
Accounts and notes receivable and accrued revenue	(17)	(61)
Inventories	171	209
Accounts payable and accrued rate refunds	(54)	(89)
Other current and non-current assets and liabilities	(3)	(12)
Net cash provided by operating activities	201	617
Cash Flows from Investing Activities
Capital expenditures (excludes assets placed under finance lease)	(523)	(481)
Increase in EnerBank notes receivable	(4)	(46)
Purchase of notes receivable by EnerBank	(8)	(121)
Cost to retire property and other investing activities	(24)	(27)
Net cash used in investing activities	(559)	(675)
Cash Flows from Financing Activities
Proceeds from issuance of debt	1,198	993
Retirement of debt	(2)	(790)
Increase (decrease) in EnerBank certificates of deposit	(7)	151
Decrease in notes payable	(90)	(67)
Issuance of common stock, net of issuance costs	101	3
Payment of dividends on common stock	(116)	(108)
Other financing costs	(22)	(32)
Net cash provided by financing activities	1,062	150
Net Increase in Cash and Cash Equivalents, Including Restricted Amounts	704	92
Cash and Cash Equivalents, Including Restricted Amounts, Beginning of Period	157	175
Cash and Cash Equivalents, Including Restricted Amounts, End of Period	861	267
Non-cash transactions
Capital expenditures not paid	95	99
Consumers Energy Company
Cash Flows from Operating Activities
Net income	235	226
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	312	294
Deferred income taxes and investment tax credits	44	17
Pension contributions	(518)	0
Other non-cash operating activities and reconciling adjustments	0	2
Cash provided by (used in) changes in assets and liabilities
Accounts and notes receivable and accrued revenue	31	(59)
Inventories	170	204
Accounts payable and accrued rate refunds	(54)	(80)
Other current and non-current assets and liabilities	18	15
Net cash provided by operating activities	238	619
Cash Flows from Investing Activities
Capital expenditures (excludes assets placed under finance lease)	(520)	(476)
Cost to retire property and other investing activities	(22)	(26)
Net cash used in investing activities	(542)	(502)
Cash Flows from Financing Activities
Proceeds from issuance of debt	873	0
Retirement of debt	0	(215)
Decrease in notes payable	(90)	(67)
Stockholder contribution	350	350
Payment of dividends on common stock	(219)	(172)
Other financing costs	(10)	(5)
Net cash provided by financing activities	904	(109)
Net Increase in Cash and Cash Equivalents, Including Restricted Amounts	600	8
Cash and Cash Equivalents, Including Restricted Amounts, Beginning of Period	28	56
Cash and Cash Equivalents, Including Restricted Amounts, End of Period	628	64
Non-cash transactions
Capital expenditures not paid	$ 85	$ 85