Consolidated Statements Of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Operating Revenue	$ 1,430	$ 1,445	$ 5,421	$ 4,830
Operating Expenses
Fuel for electric generation	161	165	534	466
Purchased and interchange power	387	383	1,244	1,063
Purchased power - related parties	21	21	67	67
Cost of gas sold	86	76	1,107	849
Maintenance and other operating expenses	329	284	899	870
Depreciation and amortization	153	145	503	463
General taxes	57	54	188	174
Total operating expenses	1,194	1,128	4,542	3,952
Operating Income	236	317	879	878
Other Income (Expense)
Interest income	1	1	2	3
Allowance for equity funds used during construction	2	1	6	5
Income from equity method investees	4	3	11	11
Other income	2	2	8	7
Other expense	(3)	(7)	(26)	(13)
Total other income	6		1	13
Interest Charges
Interest on long-term debt	98	96	294	289
Other interest expense	4	3	12	12
Allowance for borrowed funds used during construction	(1)		(3)	(2)
Total interest charges	101	99	303	299
Income Before Income Taxes	141	218	577	592
Income Tax Expense	47	91	195	240
Net Income	94	127	382	352
Income Attributable to Noncontrolling Interests		1	1	2
Net Income Available to Common Stockholders	94	126	381	350
Basic Earnings Per Average Common Share	$ 0.34	$ 0.48	$ 1.41	$ 1.32
Diluted Earnings Per Average Common Share	$ 0.34	$ 0.46	$ 1.39	$ 1.29
Dividends Declared Per Common Share	$ 0.27	$ 0.255	$ 0.81	$ 0.765
Consumers Energy Company [Member]
Operating Revenue	1,359	1,386	5,128	4,647
Operating Expenses
Fuel for electric generation	137	148	455	406
Purchased and interchange power	382	374	1,214	1,043
Purchased power - related parties	21	21	67	67
Cost of gas sold	71	64	1,006	818
Maintenance and other operating expenses	296	269	834	824
Depreciation and amortization	152	143	498	459
General taxes	55	53	183	170
Total operating expenses	1,114	1,072	4,257	3,787
Operating Income	245	314	871	860
Other Income (Expense)
Interest income	1		2	2
Interest and dividend income - related parties	1	1	1	1
Allowance for equity funds used during construction	2	1	6	5
Other income	2	2	8	11
Other expense	(3)	(3)	(13)	(9)
Total other income	3	1	4	10
Interest Charges
Interest on long-term debt	62	58	180	177
Other interest expense	3	2	8	8
Allowance for borrowed funds used during construction	(1)		(3)	(2)
Total interest charges	64	60	185	183
Income Before Income Taxes	184	255	690	687
Income Tax Expense	65	102	241	272
Net Income	119	153	449	415
Preferred Stock Dividends and Distribution		1	1	2
Net Income Available to Common Stockholders	$ 119	$ 152	$ 448	$ 413