Expected Power Generating Capacity

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- Definition

Number Of Phases Of Construction

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- Definition

Percentage Of Ownership Interests Acquired

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- Definition

Period Of Construction

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- Definition

Power Utilization

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- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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-Name Regulation S-X (SX)

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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UNCONSOLIDATED INVESTMENTS - Additional Information (Detail) (USD $) In Millions, unless otherwise specified				9 Months Ended
	Aug. 02, 2010 Mammoth Pacific	Aug. 01, 2010 Mammoth Pacific	Oct. 31, 2010 Watts And More Ltd	Sep. 30, 2011 Minimum Sarulla MW	Sep. 30, 2011 Sarulla MW Phase	Sep. 30, 2011 Sarulla Maximum MW
Schedule of Equity Method Investments [Line Items]
Equity method investments cost			$ 2.0
Ownership interest		50.00%	28.60%
Acquired ownership interest	50.00%
Ownership share					12.75%
Expected generating capacity					330
Number of phases of construction					3
Period of construction						5 years
Power utilization				110		120