Expiration Year Of Gas Sale And Purchase Agreement

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- Definition

Number Of Lease Acres

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- Definition

Number Of Lease Acres Held By Unit

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Number Of Lease Acres In Unit / Participating Area

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- Definition

Number Of Miles From Anchorage

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- Definition

Oil and Gas Delivery Commitments and Contracts, Lifted Volume

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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No definition available.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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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.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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-Name Accounting Standards Codification
-Topic 980
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- Definition

Total available amounts expected to be received from each oil producing property.

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-Name Regulation S-K (SK)
-Number 229
-Section 1207
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- Definition

Total amount of product committed to be supplied under existing contracts or agreements.

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- Definition

Net quantities of an enterprise's interests in proved developed reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas as of the beginning and the end of the year. "Net" quantities of reserves include those relating to the enterprise's operating and nonoperating interests in properties. Quantities of reserves relating to royalty interests owned are included in "net" quantities if the necessary information is available to the enterprise. "Net" quantities does not include reserves relating to interests of others in properties owned by the enterprise. The unit of measure for reserve quantities is defined as "barrels" for oil and synthetic oil reserves or "cubic feet" or "cubic meters" for natural gas and synthetic gas reserves.

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The total amount of regulated operating revenues recognized during the period.

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Beluga River Unit (Narrative) (Details)		3 Months Ended								12 Months Ended
Beluga River Unit (Narrative) (Details)	Feb. 04, 2016 USD ($) a Mcf	Dec. 31, 2016 USD ($) Mcf	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) mi Mcf	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Revenue		$ 57,741,954	$ 45,132,973	$ 44,622,517	$ 50,250,135	$ 50,640,703	$ 43,109,512	$ 47,697,820	$ 74,973,117	$ 197,747,579	$ 216,421,152	$ 281,318,513
Beluga River Unit [Member]
Business Acquisition [Line Items]
Date of Purchase and Sale Agreement										Feb. 04, 2016
Total purchase price	$ 148,000,000
Cash consideration		$ 44,403,922								$ 44,403,922
Working interest ownership percentage	30.00%	10.00%								10.00%
Number of lease acres \| a	15,500
Number of lease acres in Unit / Participating Area \| a	8,200
Number of lease acres held by Unit \| a	7,300
Number of miles from Anchorage \| mi										35
Acquisition costs		$ 1,500,000								$ 1,500,000
Amount of gas acquired \| Mcf	69,099	84								84
Revenue										$ 2,800,000
Lifted amount of gas in proven developed reserves \| Mcf		1,900,000								1,900,000
Remaining amount of gas in proven developed reserves \| Mcf		25,100,000								25,100,000
Estimated useful life										18 years
Proved developed producing reserves \| Mcf		27,000,000								27,000,000
Municipal Light & Power [Member] \| Beluga River Unit [Member]
Business Acquisition [Line Items]
Working interest ownership percentage	70.00%	56.70%								56.70%
ConocoPhillips (COP) [Member] \| Beluga River Unit [Member]
Business Acquisition [Line Items]
Working interest ownership percentage		33.30%								33.30%
ConocoPhillips (COP) [Member] \| Deep Oil Resources [Member]
Business Acquisition [Line Items]
Working interest ownership percentage	67.00%
Hilcorp Alaska, LLC [Member] \| Beluga River Unit [Member]
Business Acquisition [Line Items]
Working interest ownership percentage		33.30%								33.30%
ENSTAR [Member] \| ConocoPhillips (COP) [Member]
Business Acquisition [Line Items]
Expiration year of Gas Sale and Purchase Agreement										2017