Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Cash Flows from Operating Activities
Net income	$ 204	$ 144
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	199	181
Deferred income taxes and investment tax credit	102	87
Postretirement benefits expense	6	47
Other non-cash operating activities	19	19
Postretirement benefits contributions	(2)	(68)
Proceeds from government grant		69
Cash provided by (used in) changes in assets and liabilities
Decrease (increase) in accounts receivable, notes receivable, and accrued revenue	(313)	(103)
Decrease (increase) in inventories	345	447
Increase (decrease) in accounts payable	117	(44)
Increase (decrease) in accrued expenses	(114)	(101)
Other current and non-current assets and liabilities	48	47
Net cash provided by operating activities	611	725
Cash Flows from Investing Activities
Capital expenditures (excludes assets placed under capital lease)	(304)	(274)
Cost to retire property	(14)	(9)
Other investing activities	(28)	(10)
Net cash used in investing activities	(346)	(293)
Cash Flows from Financing Activities
Proceeds from issuance of long-term debt	550	250
Proceeds from (retirements of) EnerBank notes, net	16	(16)
Issuance of common stock	33	24
Retirement of long-term debt	(26)	(10)
Payment of common stock dividends	(72)	(67)
Increase (decrease) in notes payable	(170)	(110)
Payment of capital lease obligations and other financing costs	(10)	(10)
Net cash provided by (used in) financing activities	321	61
Net Increase (Decrease) in Cash and Cash Equivalents	586	493
Cash and Cash Equivalents, Beginning of Period	172	93
Cash and Cash Equivalents, End of Period	758	586
Consumers Energy Company [Member]
Cash Flows from Operating Activities
Net income	221	162
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	197	180
Deferred income taxes and investment tax credit	46	44
Postretirement benefits expense	6	47
Other non-cash operating activities	16	18
Postretirement benefits contributions	(1)	(67)
Proceeds from government grant		69
Cash provided by (used in) changes in assets and liabilities
Decrease (increase) in accounts receivable, notes receivable, and accrued revenue	(303)	(102)
Decrease (increase) in inventories	338	442
Increase (decrease) in accounts payable	120	(44)
Increase (decrease) in accrued expenses	(43)	(80)
Other current and non-current assets and liabilities	49	44
Net cash provided by operating activities	646	713
Cash Flows from Investing Activities
Capital expenditures (excludes assets placed under capital lease)	(302)	(273)
Cost to retire property	(14)	(9)
Other investing activities	1	(13)
Net cash used in investing activities	(315)	(295)
Cash Flows from Financing Activities
Retirement of long-term debt	(11)	(10)
Payment of common stock dividends	(135)	(93)
Stockholder contribution	150	150
Increase (decrease) in notes payable	(170)	(110)
Payment of capital lease obligations and other financing costs	(5)	(5)
Net cash provided by (used in) financing activities	(171)	(68)
Net Increase (Decrease) in Cash and Cash Equivalents	160	350
Cash and Cash Equivalents, Beginning of Period	18	5
Cash and Cash Equivalents, End of Period	$ 178	$ 355

Cash grant received from government during the current period.

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- Definition

The aggregate amount of adjustments to net income or loss necessary to remove the effects of all items whose cash effects are investing or financing cash flows. The aggregate amount also includes all noncash expenses and income items which reduce or increase net income and are thus added back or deducted when calculating cash provided by or used in operating activities.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of deferred income tax expense (benefit) and income tax credits.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The increase (decrease) during the reporting period in the amount due from customers for the credit sale of goods and services; includes accounts receivable and other types of receivables.

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