v2.3.0.15

Fair Value Measurements, Fair Value Hierarchy Table (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Millions | Sep. 30, 2011 | Dec. 31, 2010
--- | --- | ---
Derivative assets |  |
Derivative assets | $ 42.2 | $ 79.1
Derivative liabilities |  |
Derivative Liabilities | 60.4 | 78.4
Aluminum Commodity [Member] | Call option purchase contracts [Member] |  |
Derivative assets |  |
Derivative assets | 0.5 | 9.3
Aluminum Commodity [Member] | Call option purchase contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Aluminum Commodity [Member] | Call option purchase contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets | 0.5 | 9.3
Aluminum Commodity [Member] | Call option purchase contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Aluminum Commodity [Member] | Call option sales contracts [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0.5 | 9.3
Aluminum Commodity [Member] | Call option sales contracts [Member] | Level 1 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Aluminum Commodity [Member] | Call option sales contracts [Member] | Level 2 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0.5 | 9.3
Aluminum Commodity [Member] | Call option sales contracts [Member] | Level 3 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Aluminum Commodity [Member] | Put option purchase contracts [Member] |  |
Derivative assets |  |
Derivative assets |  | 0.1
Aluminum Commodity [Member] | Put option purchase contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0
Aluminum Commodity [Member] | Put option purchase contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0.1
Aluminum Commodity [Member] | Put option purchase contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0
Aluminum Commodity [Member] | Put option sales contracts [Member] |  |
Derivative liabilities |  |
Derivative Liabilities |  | 0.1
Aluminum Commodity [Member] | Put option sales contracts [Member] | Level 1 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities |  | 0
Aluminum Commodity [Member] | Put option sales contracts [Member] | Level 2 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities |  | 0.1
Aluminum Commodity [Member] | Put option sales contracts [Member] | Level 3 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities |  | 0
Aluminum Commodity [Member] | Fixed priced purchase contracts [Member] |  |
Derivative assets |  |
Derivative assets | 1.4 | 18.2
Derivative liabilities |  |
Derivative Liabilities | 5.7 | 0.4
Aluminum Commodity [Member] | Fixed priced purchase contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Aluminum Commodity [Member] | Fixed priced purchase contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets | 1.4 | 18.2
Derivative liabilities |  |
Derivative Liabilities | 5.7 | 0.4
Aluminum Commodity [Member] | Fixed priced purchase contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Aluminum Commodity [Member] | Fixed priced sales contracts [Member] |  |
Derivative assets |  |
Derivative assets | 0.5 |
Derivative liabilities |  |
Derivative Liabilities | 0.4 | 3.4
Aluminum Commodity [Member] | Fixed priced sales contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets | 0 |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Aluminum Commodity [Member] | Fixed priced sales contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets | 0.5 |
Derivative liabilities |  |
Derivative Liabilities | 0.4 | 3.4
Aluminum Commodity [Member] | Fixed priced sales contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets | 0 |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Aluminum Commodity [Member] | Midwest premium swap contracts [Member] |  |
Derivative assets |  |
Derivative assets | 0.7 | 0.2
Derivative liabilities |  |
Derivative Liabilities |  | 0.1
Aluminum Commodity [Member] | Midwest premium swap contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Derivative liabilities |  |
Derivative Liabilities |  | 0
Aluminum Commodity [Member] | Midwest premium swap contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Derivative liabilities |  |
Derivative Liabilities |  | 0
Aluminum Commodity [Member] | Midwest premium swap contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets | 0.7 | 0.2
Derivative liabilities |  |
Derivative Liabilities |  | 0.1
Natural Gas [Member] | Call option purchase contracts [Member] |  |
Derivative assets |  |
Derivative assets |  | 0.3
Derivative liabilities |  |
Derivative Liabilities | 0.1 |
Natural Gas [Member] | Call option purchase contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0
Derivative liabilities |  |
Derivative Liabilities | 0 |
Natural Gas [Member] | Call option purchase contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0.3
Derivative liabilities |  |
Derivative Liabilities | 0.1 |
Natural Gas [Member] | Call option purchase contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0
Derivative liabilities |  |
Derivative Liabilities | 0 |
Natural Gas [Member] | Put option purchase contracts [Member] |  |
Derivative assets |  |
Derivative assets | 0.9 | 2.5
Natural Gas [Member] | Put option purchase contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Natural Gas [Member] | Put option purchase contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets | 0.9 | 2.5
Natural Gas [Member] | Put option purchase contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Natural Gas [Member] | Put option sales contracts [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 4.0 | 4.6
Natural Gas [Member] | Put option sales contracts [Member] | Level 1 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Natural Gas [Member] | Put option sales contracts [Member] | Level 2 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 4.0 | 4.6
Natural Gas [Member] | Put option sales contracts [Member] | Level 3 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Natural Gas [Member] | Fixed priced purchase contracts [Member] |  |
Derivative assets |  |
Derivative assets |  | 0.1
Derivative liabilities |  |
Derivative Liabilities | 0.9 | 0.5
Natural Gas [Member] | Fixed priced purchase contracts [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Natural Gas [Member] | Fixed priced purchase contracts [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0.1
Derivative liabilities |  |
Derivative Liabilities | 0.9 | 0.5
Natural Gas [Member] | Fixed priced purchase contracts [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets |  | 0
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Electricity [Member] | Fixed priced purchase contracts [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 1.2 |
Electricity [Member] | Fixed priced purchase contracts [Member] | Level 1 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 |
Electricity [Member] | Fixed priced purchase contracts [Member] | Level 2 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 1.2 |
Electricity [Member] | Fixed priced purchase contracts [Member] | Level 3 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 |
Hedges Relating to Notes [Member] | Bifurcated Conversion Feature [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 47.6 | 60.0
Hedges Relating to Notes [Member] | Bifurcated Conversion Feature [Member] | Level 1 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Hedges Relating to Notes [Member] | Bifurcated Conversion Feature [Member] | Level 2 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 47.6 | 60.0
Hedges Relating to Notes [Member] | Bifurcated Conversion Feature [Member] | Level 3 [Member] |  |
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Hedges Relating to Notes [Member] | Call Options [Member] |  |
Derivative assets |  |
Derivative assets | 38.2 | 48.4
Hedges Relating to Notes [Member] | Call Options [Member] | Level 1 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Hedges Relating to Notes [Member] | Call Options [Member] | Level 2 [Member] |  |
Derivative assets |  |
Derivative assets | 38.2 | 48.4
Hedges Relating to Notes [Member] | Call Options [Member] | Level 3 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Level 1 [Member] |  |
Derivative assets |  |
Derivative assets | 0 | 0
Derivative liabilities |  |
Derivative Liabilities | 0 | 0
Level 2 [Member] |  |
Derivative assets |  |
Derivative assets | 41.5 | 78.9
Derivative liabilities |  |
Derivative Liabilities | 60.4 | 78.3
Level 3 [Member] |  |
Derivative assets |  |
Derivative assets | 0.7 | 0.2
Derivative liabilities |  |
Derivative Liabilities | $ 0 | $ 0.1

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