Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Current Assets
Cash and cash equivalents	$ 493	$ 172
Restricted cash and cash equivalents	37	32
Accounts receivable and accrued revenue, less allowances	683	914
Notes receivable	96	63
Accounts receivable - related parties	11	10
Accrued power supply and gas revenue	109
Inventories at average cost
Gas in underground storage	833	660
Materials and supplies	114	107
Generating plant fuel stock	96	114
Deferred income taxes	48	126
Deferred property taxes	128	202
Regulatory assets	7	40
Prepayments and other current assets	79	86
Total current assets	2,734	2,526
Plant, Property, and Equipment
Plant, property, and equipment, gross	17,155	16,184
Less accumulated depreciation and amortization	5,321	5,087
Plant, property, and equipment, net	11,834	11,097
Construction work in progress	1,211	1,149
Total plant, property, and equipment	13,045	12,246
Other Non-current Assets
Regulatory assets	1,447	1,530
Accounts and notes receivable, less allowances	759	646
Investments	61	59
Other	335	409
Total other non-current assets	2,602	2,644
Total Assets	18,381	17,416
Current Liabilities
Current portion of long-term debt, capital leases, and financing obligation	690	562
Notes payable		170
Accounts payable	604	585
Accounts payable - related parties	9	10
Accrued rate refunds		12
Accrued interest	65	96
Accrued taxes	89	297
Regulatory liabilities	67	67
Other current liabilities	124	146
Total current liabilities	1,648	1,945
Non-current Liabilities
Long-term debt	8,042	7,101
Non-current portion of capital leases and financing obligations	129	138
Regulatory liabilities	2,189	2,215
Postretirement benefits	242	239
Asset retirement obligations	330	325
Deferred investment tax credit	38	40
Deferred income taxes	1,749	1,616
Other non-current liabilities	307	306
Total non-current liabilities	13,026	11,980
Commitments and Contingencies (Notes 2 and 3)
Equity
Common stock	3	3
Other paid-in capital	4,767	4,715
Accumulated other comprehensive income (loss)	(20)	(22)
Retained earnings (Accumulated deficit)	(1,080)	(1,242)
Total common stockholder's equity	3,670	3,454
Noncontrolling interests	37	37
Total equity	3,707	3,491
Total Liabilities and Equity	18,381	17,416
Consumers Energy Company [Member]
Current Assets
Cash and cash equivalents	200	18
Restricted cash and cash equivalents	37	31
Accounts receivable and accrued revenue, less allowances	669	902
Notes receivable		14
Accounts receivable - related parties	1	4
Accrued power supply and gas revenue	109
Inventories at average cost
Gas in underground storage	833	653
Materials and supplies	110	103
Generating plant fuel stock	89	113
Deferred property taxes	128	202
Regulatory assets	7	40
Prepayments and other current assets	73	77
Total current assets	2,256	2,157
Plant, Property, and Equipment
Plant, property, and equipment, gross	17,013	16,044
Less accumulated depreciation and amortization	5,252	5,022
Plant, property, and equipment, net	11,761	11,022
Construction work in progress	1,208	1,147
Total plant, property, and equipment	12,969	12,169
Other Non-current Assets
Regulatory assets	1,447	1,530
Accounts and notes receivable, less allowances	7	11
Investments	32	29
Other	208	283
Total other non-current assets	1,694	1,853
Total Assets	16,919	16,179
Current Liabilities
Current portion of long-term debt, capital leases, and financing obligation	81	64
Notes payable		170
Accounts payable	591	571
Accounts payable - related parties	11	13
Accrued rate refunds		12
Accrued interest	45	63
Accrued taxes	159	353
Deferred income taxes	108	55
Regulatory liabilities	67	67
Other current liabilities	99	112
Total current liabilities	1,161	1,480
Non-current Liabilities
Long-term debt	5,230	4,579
Non-current portion of capital leases and financing obligations	129	138
Regulatory liabilities	2,189	2,215
Postretirement benefits	183	179
Asset retirement obligations	329	324
Deferred investment tax credit	38	40
Deferred income taxes	2,166	2,115
Other non-current liabilities	243	252
Total non-current liabilities	10,507	9,842
Commitments and Contingencies (Notes 2 and 3)
Equity
Common stock	841	841
Other paid-in capital	3,574	3,257
Accumulated other comprehensive income (loss)	2	(2)
Retained earnings (Accumulated deficit)	797	724
Total common stockholder's equity	5,214	4,820
Preferred stock	37	37
Total equity	5,251	4,857
Total Liabilities and Equity	$ 16,919	$ 16,179