|
Earnings Per Share - CMS Energy (Convertible Debentures) (Details) (USD $)
In Millions, unless otherwise specified |
9 Months Ended | |
|---|---|---|
|
Sep. 30, 2012
|
Sep. 30, 2011
|
|
|
Convertible Debt Securities [Member]
|
||
| Interest rate | 7.75% | 7.75% |
| Potential impact of antidilutive debentures - income | $ 1.0 | |
| Potential impact of antidilutive debentures - shares | 0.2 | 0.7 |
|
Debt Retirements [Member] | Trust Preferred Securities [Member]
|
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| Debt retirement date | February 2012 | February 2012 |