The amount of on sale or disposal of finite lived intangible assets.

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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-Section 45
-Paragraph 2
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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

The increase (decrease) during the reporting period in intangible assets (for example patents and licenses).

+ References

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Note 9 - Intangible Assets and Goodwill (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 15, 2017
Finite-Lived Intangible Assets, Net, Ending Balance	$ 85,420
Amortization of Intangible Assets, Total	6,900	$ 4,400	$ 3,300
Increase (Decrease) in Intangible Assets, Current	35,600	33,000	500
Finite Lived Intangible Assets, Disposals	0	2,016,000	$ 0
Goodwill, Ending Balance	21,037	6,650
Viridity Energy, Inc. [Member]
Goodwill, Ending Balance				$ 13,400
Goodwill, Acquired During Period	13,500
Guadeloupe Power Plant Transaction [Member]
Goodwill, Acquired During Period		7,100
Power Purchase Agreements and Intangible Assets Related to Storage Activities [Member]
Finite-Lived Intangible Assets, Net, Ending Balance	85,400	52,800
Finite-Lived Intangible Assets, Accumulated Amortization	50,000	$ 42,800
Intangible Assets Related to Storage Activities [Member]
Finite-Lived Intangible Assets, Net, Ending Balance	33,800
Finite-Lived Intangible Assets, Accumulated Amortization	$ 1,700