Amount of assets in group for testing long-lived assets for impairment.

No definition available.

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- Definition

Represents the number of projects supplying steam to the U.S. Navy.

+ References

No definition available.

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- Definition

The useful life of the power project in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

It represents the amount of net working capital.

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No definition available.

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No definition available.

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

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- Definition

Amount recognized as an operating expense or loss during the period to reduce the carrying amount of a project that has been impaired but not abandoned.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

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.

+ References

No definition available.

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Property, plant and equipment, net - Impairments (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) project
Asset Impairment Charges [Abstract]
Impairment of property, plant and equipment	$ 4.0	$ 0.0	$ 67.6
Impairment of Ongoing Project	55.0		187.1
Calstock
Asset Impairment Charges [Abstract]
Asset group for testing long-lived assets	7.8
Net working capital	2.3
Impairment of Ongoing Project	4.7
Impairment of intangible assets related to PPAs	0.7
Partial impairment of PP&E	4.0
Impairment losses related to spare parts inventory	1.1
Calstock \| Property, Plant and Equipment
Asset Impairment Charges [Abstract]
Impairment of intangible assets related to PPAs	4.7
Calstock \| Power Purchase agreements
Asset Impairment Charges [Abstract]
Impairment of intangible assets related to PPAs	$ 0.8
Williams Lake
Asset Impairment Charges [Abstract]
Impairment of property, plant and equipment		0.0
Asset group for testing long-lived assets		$ 11.4	$ 40.0
Remaining useful life of the project		20 years	22 years
Impairment of Ongoing Project			$ 29.1
Impairment of intangible assets related to PPAs			0.6
Williams Lake \| Property, Plant and Equipment
Asset Impairment Charges [Abstract]
Asset group for testing long-lived assets			39.4
Partial impairment of PP&E			28.5
Williams Lake \| Power Purchase agreements
Asset Impairment Charges [Abstract]
Asset group for testing long-lived assets			$ 0.6
San Diego Projects
Property, Plant and Equipment [Line Items]
Number of projects supplying steam \| project			3
Asset Impairment Charges [Abstract]
Impairment of Ongoing Project			$ 57.3
San Diego Projects \| Property, Plant and Equipment
Asset Impairment Charges [Abstract]
Partial impairment of PP&E			39.1
San Diego Projects \| Power Purchase agreements
Asset Impairment Charges [Abstract]
Impairment of intangible assets related to PPAs			18.2
Naval Station
Asset Impairment Charges [Abstract]
Impairment of Ongoing Project			22.5
Naval Station \| Property, Plant and Equipment
Asset Impairment Charges [Abstract]
Partial impairment of PP&E			12.1
Naval Station \| Power Purchase agreements
Asset Impairment Charges [Abstract]
Impairment of intangible assets related to PPAs			10.3
Naval Training Center
Asset Impairment Charges [Abstract]
Impairment of Ongoing Project			13.5
Naval Training Center \| Property, Plant and Equipment
Asset Impairment Charges [Abstract]
Partial impairment of PP&E			9.9
Naval Training Center \| Power Purchase agreements
Asset Impairment Charges [Abstract]
Impairment of intangible assets related to PPAs			3.6
North Island
Asset Impairment Charges [Abstract]
Impairment of Ongoing Project			21.2
North Island \| Property, Plant and Equipment
Asset Impairment Charges [Abstract]
Partial impairment of PP&E			17.0
North Island \| Power Purchase agreements
Asset Impairment Charges [Abstract]
Impairment of intangible assets related to PPAs			$ 4.2