Estimated entitled additional energy output percentage.

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- Definition

Estimated increase in annual energy output.

+ References

No definition available.

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- Definition

Long Term Contract For Purchase Of Electric Power Share Of Plant Output Being Purchased, Energy

+ References

No definition available.

+ Details

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- Definition

Threshold percentage for increasing plant costs.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Under long-term contracts with public utility districts, cooperatives or other organizations, a utility company receives a portion of the output of a production plant constructed and financed by the district or cooperative. The utility has only a nominal or no investment at all in the plant but pays a proportionate part of the plant's costs, including debt service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.D)
-URI http://asc.fasb.org/extlink&oid=6499423&loc=d3e659339-123030

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- Definition

Estimated annual cost to purchase electricity under a long-term contract from a production plant constructed and financed by a public utility district, cooperative, or other organization.

+ References

+ Details

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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.

+ Details

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- Definition

Share of plant output being purchased under a long-term contract to purchase electricity from a production plant constructed and financed by a public utility district, cooperative, or other organization.

+ References

+ Details

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- Definition

Amount of operating expense for purchased power of regulated operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(b))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Bradley Lake Hydroelectric Project (Narrative) (Details)	12 Months Ended
	Dec. 31, 2016 USD ($) MWh MW	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Long-term Contract for Purchase of Electric Power [Line Items]
Purchased power	$ 15,774,733	$ 19,599,994	$ 15,608,396
Bradley Lake Hydroelectric Project [Member]
Long-term Contract for Purchase of Electric Power [Line Items]
Percentage share of power purchased	30.40%
Amount of committed purchased power \| MW	27.4
Threshold percentage for increasing plant costs	25.00%
Estimated entitled additional energy output percentage	30.40%
Purchased power	$ 5,662,522	$ 5,663,304	$ 5,228,907
Revenue Bonds [Member] \| Alaska Energy Authority [Member] \| Bradley Lake Hydroelectric Project [Member]
Long-term Contract for Purchase of Electric Power [Line Items]
Bonds issuance amount	166,000,000
Portion of outstanding debt	19,000,000
Possible annual expenditures upon default	$ 6,000,000
Maximum [Member] \| Bradley Lake Hydroelectric Project [Member]
Long-term Contract for Purchase of Electric Power [Line Items]
Estimated increase in annual energy output \| MWh	40,000