Derivative Financial Instruments and Related Hedging Programs, Notional Quantity Table (Details) (EUR €) | Sep. 30, 2011
mmlbs | |||||||
|---|---|---|---|---|---|---|---|---|
Aluminum Commodity [Member] | Call option purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 12.2 | |||||||
Aluminum Commodity [Member] | Call option sales contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 12.2 | |||||||
Aluminum Commodity [Member] | Put option purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 25.4 | |||||||
Aluminum Commodity [Member] | Put option sales contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 12.2 | |||||||
Aluminum Commodity [Member] | Fixed priced purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 78.4 | |||||||
Aluminum Commodity [Member] | Fixed priced sales contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 6.0 | |||||||
Aluminum Commodity [Member] | Midwest premium swap contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 38.0 | [1] | ||||||
Natural Gas [Member] | Call option purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 4,740,000 | [2] | ||||||
Natural Gas [Member] | Call option sales contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 690,000 | [2] | ||||||
Natural Gas [Member] | Put option purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 690,000 | [2] | ||||||
Natural Gas [Member] | Put option sales contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 4,740,000 | [2] | ||||||
Natural Gas [Member] | Fixed priced purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 1,920,000 | [2] | ||||||
Electricity [Member] | Fixed priced purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 219,600 | |||||||
Foreign Currency [Member] | Euros [Member] | Fixed priced purchase contracts [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts (Foreign Currency) | 117,500 | |||||||
Hedges Relating to Notes [Member] | Bifurcated Conversion Feature [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 3,621,608 | [3] | ||||||
Hedges Relating to Notes [Member] | Call Options [Member] | ||||||||
| Summary of material derivative positions | ||||||||
| Notional Amount of Contracts | 3,621,608 | [3] | ||||||
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