Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Current Assets
Cash and cash equivalents	$ 207		$ 172
Restricted cash and cash equivalents	37		32
Accounts receivable and accrued revenue, less allowances	881		914
Notes receivable	98		63
Notes receivable held for sale	41
Accounts receivable - related parties	11		10
Accrued gas revenue	27
Inventories at average cost
Gas in underground storage	681		660
Materials and supplies	117		107
Generating plant fuel stock	120		114
Deferred income taxes			126
Deferred property taxes	216		202
Regulatory assets	89		40
Prepayments and other current assets	72		86
Total current assets	2,597		2,526
Plant, Property, and Equipment
Plant, property, and equipment, gross	17,721		16,184
Less accumulated depreciation and amortization	5,415		5,087
Plant, property, and equipment, net	12,306		11,097
Construction work in progress	1,106		1,149
Total plant, property, and equipment	13,412	[1]	12,246	[1]
Other Non-current Assets
Regulatory assets	1,956		1,530
Accounts and notes receivable, less allowances	807		646
Investments	61	[2]	59	[2]
Other	352		409
Total other non-current assets	3,176		2,644
Total Assets	19,185		17,416
Current Liabilities
Current portion of long-term debt, capital leases, and financing obligation	540		562
Notes payable	60		170
Accounts payable	678		585
Accounts payable - related parties	10		10
Accrued rate refunds	6		12
Accrued interest	108		96
Accrued taxes	316		297
Deferred income taxes	66
Regulatory liabilities	67		67
Other current liabilities	163		146
Total current liabilities	2,014		1,945
Non-current Liabilities
Long-term debt	8,016		7,101
Non-current portion of capital leases and financing obligation	123		138
Regulatory liabilities	2,095		2,215
Postretirement benefits	872		239
Asset retirement obligations	340		325
Deferred investment tax credit	37		40
Deferred income taxes	1,682		1,616
Other non-current liabilities	299		306
Total non-current liabilities	13,464		11,980
Commitments and Contingencies (Notes 3, 4, 5, and 7)
Equity
Common stock	3		3
Other paid-in capital	4,774		4,715
Accumulated other comprehensive loss	(49)		(22)
Retained earnings (Accumulated deficit)	(1,058)		(1,242)
Total common stockholders' equity	3,670		3,454
Noncontrolling interests	37		37
Total equity	3,707		3,491
Total Liabilities and Equity	19,185		17,416
Consumers Energy Company [Member]
Current Assets
Cash and cash equivalents	71		18
Restricted cash and cash equivalents	37		31
Accounts receivable and accrued revenue, less allowances	863		902
Notes receivable			14
Accounts receivable - related parties	1		4
Accrued gas revenue	27
Inventories at average cost
Gas in underground storage	681		653
Materials and supplies	113		103
Generating plant fuel stock	112		113
Deferred property taxes	216		202
Regulatory assets	89	[3]	40	[3]
Prepayments and other current assets	63		77
Total current assets	2,273		2,157
Plant, Property, and Equipment
Plant, property, and equipment, gross	17,580		16,044
Less accumulated depreciation and amortization	5,346		5,022
Plant, property, and equipment, net	12,234		11,022
Construction work in progress	1,103		1,147
Total plant, property, and equipment	13,337	[1]	12,169	[1]
Other Non-current Assets
Regulatory assets	1,956		1,530
Accounts and notes receivable, less allowances	7		11
Investments	38		29
Other	236		283
Total other non-current assets	2,237		1,853
Total Assets	17,847		16,179
Current Liabilities
Current portion of long-term debt, capital leases, and financing obligation	145		64
Notes payable	60		170
Accounts payable	662		571
Accounts payable - related parties	12		13
Accrued rate refunds	6		12
Accrued interest	70		63
Accrued taxes	149		353
Deferred income taxes	80		55
Regulatory liabilities	67		67
Other current liabilities	135		112
Total current liabilities	1,386		1,480
Non-current Liabilities
Long-term debt	5,154		4,579
Non-current portion of capital leases and financing obligation	123		138
Regulatory liabilities	2,095		2,215
Postretirement benefits	793		179
Asset retirement obligations	339		324
Deferred investment tax credit	37		40
Deferred income taxes	2,406		2,115
Other non-current liabilities	237		252
Total non-current liabilities	11,184		9,842
Commitments and Contingencies (Notes 3, 4, 5, and 7)
Equity
Common stock	841		841
Other paid-in capital	3,574		3,257
Accumulated other comprehensive loss	(7)		(2)
Retained earnings (Accumulated deficit)	832		724
Total common stockholders' equity	5,240		4,820
Preferred stock	37		37
Total equity	5,277		4,857
Total Liabilities and Equity	$ 17,847		$ 16,179

[1] For the year ended December 31, 2014, utility plant additions were $1.6 billion and utility plant retirements were $126 million. For the year ended December 31, 2013, utility plant additions were $1.3 billion and utility plant retirements were $156 million.

[2] Consumers had no significant equity method investments.

[3] This regulatory asset is offset partially by liabilities. The net amount is included in rate base, thereby providing a return.