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Represents the amount of equity method distributions since the acquisition date included in the consolidated income statement for the reporting period.

No definition available.

Name:	at_BusinessCombinationEquityMethodDistributionsSinceAcquisitionDateActual
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The number of biomass plants acquired or to be acquired per agreement.

No definition available.

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Capacity of the plants acquired.

No definition available.

Name:	at_PlantCapacity
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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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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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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

No definition available.

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Data Type:	num:percentItemType
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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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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.

No definition available.

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