XML 144 R129.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Reportable Segments (Reconciliation of Assets from Segment to Consolidated) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2011 | Sep. 30, 2011 | Jun. 30, 2011 | Mar. 31, 2011 | Dec. 31, 2010 | Sep. 30, 2010 | Jun. 30, 2010 | Mar. 31, 2010 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Operating Revenue | $ 1,620 |  | $ 1,464 | $ 1,364 | $ 2,055 | $ 1,682 |  | $ 1,443 | $ 1,340 | $ 1,967 | $ 6,503 |  | $ 6,432 |  | $ 6,205 |
Operating Income | 174 |  | 316 | 207 | 306 | 158 |  | 319 | 262 | 239 | 1,003 |  | 978 |  | 698 |
Total Assets | 16,452 | [1] |  |  |  | 15,616 | [1] |  |  |  | 16,452 | [1] | 15,616 | [1] | 15,256 | [1]
Consumers Energy Company [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue | 1,565 |  | 1,397 | 1,303 | 1,988 | 1,620 |  | 1,370 | 1,276 | 1,890 | 6,253 |  | 6,156 |  | 5,963 |
Operating Income | 173 |  | 305 | 207 | 300 | 191 |  | 304 | 207 | 224 | 985 |  | 926 |  | 689 |
Total Assets | 15,662 | [1] |  |  |  | 14,839 | [1] |  |  |  | 15,662 | [1] | 14,839 | [1] | 14,622 | [1]
International [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Operating Income |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Total Assets | 1 |  |  |  |  | 3 |  |  |  |  | 1 |  | 3 |  | 3 |
International [Member] | Consumers Energy Company [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenue |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Operating Income |  |  |  |  |  |  |  |  |  |  | 0 |  | 0 |  | 0 |
Total Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |
[1] | Amounts include a portion of Consumers' other common assets attributable to both the electric and gas utility businesses.

X
- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 7 -Section 03 -Paragraph 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Topic 210 -SubTopic 10 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 -Section S99 -Name Accounting Standards Codification -Publisher FASB -Paragraph 1 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.18) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_Assets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The net result for the period of deducting operating expenses from operating revenues. + References No definition available. + Details
Name: | us-gaap_OperatingIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 5 -Section 03 -Paragraph 1 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 + Details
Name: | us-gaap_Revenues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration