Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Assets
Cash and cash equivalents	$ 161		$ 247
Restricted cash and cash equivalents	27		23
Accounts receivable and accrued revenue, less allowances	869		981
Notes receivable	49		70
Accounts receivable - related parties	10		10
Accrued power supply revenue	0		15
Inventories at average cost
Gas in underground storage	929		946
Materials and supplies	92		104
Generating plant fuel stock	166		125
Deferred income taxes	24		0
Deferred property taxes	187		180
Regulatory assets	1		19
Assets held for sale	0		2
Prepayments and other current assets	50		37
Total current assets	2,565		2,759
Plant, Property, and Equipment (at cost)
Plant, property, and equipment, gross	14,751		14,145
Less accumulated depreciation and amortization	4,901		4,646
Plant, property and equipment, net	9,850		9,499
Construction work in progress	783		570
Total plant, property, and equipment	10,633	[1]	10,069	[1]
Other Non-current Assets
Regulatory assets	2,466		2,093
Accounts and notes receivable, less allowances	462		397
Investments	50		49
Assets held for sale			4
Other	276		245
Total other non-current assets	3,254		2,788
Total Assets	16,452	[2]	15,616	[2]
Liabilities and Equity
Current portion of long-term debt, capital and finance lease obligations	1,057		750
Accounts payable	575		492
Accounts payable - related parties	9		9
Accrued rate refunds	30		19
Accrued interest	101		102
Accrued taxes	282		302
Deferred income taxes	0		180
Regulatory liabilities	125		22
Liabilities held for sale			1
Other current liabilities	159		144
Total current liabilities	2,338		2,021
Non-current Liabilities
Long-term debt	6,040		6,448
Non-current portion of capital and finance lease obligations	167		188
Regulatory liabilities	1,875		1,988
Postretirement benefits	1,289		1,135
Asset retirement obligations	254		245
Deferred investment tax credit	46		49
Deferred income taxes	1,035		438
Other non-current liabilities	336		267
Total non-current liabilities	11,042		10,758
Commitments and Contingencies (Notes 5,6,7,9, and 10)
Equity
Common stock	3		2
Other paid-in capital	4,627		4,588
Accumulated other comprehensive loss	(49)		(40)
Retained earnings (Accumulated deficit)	(1,553)		(1,757)
Total common stockholders' equity	3,028		2,793
Noncontrolling interests	44		44
Total equity	3,072		2,837
Total Liabilities and Equity	16,452		15,616
Consumers Energy Company [Member]
Assets
Cash and cash equivalents	85		71
Restricted cash and cash equivalents	26		23
Accounts receivable and accrued revenue, less allowances	860		963
Notes receivable	23		55
Accounts receivable - related parties	1		1
Accrued power supply revenue	0		15
Inventories at average cost
Gas in underground storage	929		941
Materials and supplies	88		100
Generating plant fuel stock	164		124
Deferred property taxes	187		180
Regulatory assets	1		19
Prepayments and other current assets	43		27
Total current assets	2,407		2,519
Plant, Property, and Equipment (at cost)
Plant, property, and equipment, gross	14,621		14,022
Less accumulated depreciation and amortization	4,846		4,593
Plant, property and equipment, net	9,775		9,429
Construction work in progress	782		566
Total plant, property, and equipment	10,557	[1]	9,995	[1]
Other Non-current Assets
Regulatory assets	2,466		2,093
Accounts and notes receivable, less allowances	1		22
Investments	35		34
Other	196		176
Total other non-current assets	2,698		2,325
Total Assets	15,662	[2]	14,839	[2]
Liabilities and Equity
Current portion of long-term debt, capital and finance lease obligations	363		61
Accounts payable	561		471
Accounts payable - related parties	11		11
Accrued rate refunds	30		19
Accrued interest	73		74
Accrued taxes	287		199
Deferred income taxes	73		209
Regulatory liabilities	125		22
Other current liabilities	119		95
Total current liabilities	1,642		1,161
Non-current Liabilities
Long-term debt	3,987		4,488
Non-current portion of capital and finance lease obligations	167		188
Regulatory liabilities	1,875		1,988
Postretirement benefits	1,225		1,076
Asset retirement obligations	253		244
Deferred investment tax credit	46		49
Deferred income taxes	1,817		1,289
Other non-current liabilities	256		176
Total non-current liabilities	9,626		9,498
Commitments and Contingencies (Notes 5,6,7,9, and 10)
Equity
Common stock	841		841
Other paid-in capital	2,957		2,832
Accumulated other comprehensive loss	(2)		0
Retained earnings (Accumulated deficit)	554		463
Total common stockholders' equity	4,350		4,136
Preferred stock	44		44
Total equity	4,394		4,180
Total Liabilities and Equity	$ 15,662		$ 14,839

[1] For the year ended December 31, 2011, utility plant additions were $700 million and utility plant retirements were $104 million. For the year ended December 31, 2010, utility plant additions were $783 million and utility plant retirements were $85 million.

[2] Amounts include a portion of Consumers' other common assets attributable to both the electric and gas utility businesses.