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Legal Contingencies [Abstract]

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Litigation Settlement, Annual Installment

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Litigation Settlement Installment Period

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Litigation Settlement Payment Period

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The number of labor unions representing a group of employees.

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Pursuant to the terms of the settlement agreement with the Pension Benefit Guaranty Corporation, we will make additional contributions (above any minimum required contributions) to our defined benefit pension plans.

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Pension Contributions, Amended Term, Total Contribution

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Pension Contributions, Term

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The percentage of a Company's work force, based in the country of domicile, that are subject to collective bargaining agreements.

No definition available.

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The percentage of a Company's Icelandic work force that are subject to collective bargaining agreements.

No definition available.

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Percentage Of Foreign Work Force, Represented By Union

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The percentage of a Company's work force that are subject to collective bargaining agreements.

No definition available.

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Power Supply Agreement, Extension Term

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Power Supply Agreement, Required Termination Period

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Ravenswood litigation [Abstract]

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Short-term Power Agreement, Supply Percentage

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The power currently available under the power purchase agreement.

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Underlying, Derivative Power, Available, Requested

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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Amount awarded to other party in judgment or settlement of litigation.

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Amount of loss contingency liability.

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Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

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Amount of liabilities classified as other.

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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

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