Commitments And Contingencies (Details)	3 Months Ended		4 Months Ended	6 Months Ended
	Jun. 30, 2016 USD ($) MMcf	Jun. 30, 2015 USD ($)	Apr. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) agreement MMcf	Jun. 30, 2015 USD ($)	Apr. 22, 2016	Feb. 04, 2016	Dec. 31, 2015 USD ($)
Other Commitments [Line Items]
Contingency accruals	$ 0			$ 0
Operating revenues	44,622,517	$ 47,697,820		94,872,652	$ 122,670,937
Patronage capital payable	11,108,071			$ 11,108,071				$ 11,108,071
Matanuska Electric Association, Inc. [Member]
Other Commitments [Line Items]
Operating revenues			$ 26,200,000
Power contracts expiration date				Apr. 30, 2015
Patronage capital payable	3,200,000			$ 3,200,000				3,200,000
Homer Electric Association, Inc. [Member]
Other Commitments [Line Items]
Power contracts expiration date				Dec. 31, 2013
Number of years to return patronage capital after expiration of power agreement				5 years
Patronage capital payable	$ 7,900,000			$ 7,900,000				$ 7,900,000
ConocoPhillips (COP) [Member]
Other Commitments [Line Items]
Commencement date of long term contract for purchase of gas supply				Aug. 21, 2009
Expiration date of long term contract for purchase of gas supply				Dec. 31, 2016
Estimated amount of gas under contract | MMcf	62,000			62,000
Hilcorp Alaska - Cook Inlet [Member]
Other Commitments [Line Items]
Commencement date of long term contract for purchase of gas supply				Jan. 01, 2015
Expiration date of long term contract for purchase of gas supply				Mar. 31, 2018
Estimated amount of gas under contract | MMcf	60,000			60,000
Percentage of met natural gas needs				100.00%
Initial extension date of long term contract for purchase of gas supply				Mar. 31, 2019
Subsequent extension date of long term contract for purchase of gas supply				Mar. 31, 2023
Beluga River Unit [Member]
Other Commitments [Line Items]
Operating revenues				$ 800,000
Estimated amount of gas under contract | MMcf	26,100			26,100
Working interest ownership percentage	10.00%			10.00%			30.00%
Beluga River Unit [Member] | Municipal Light & Power [Member]
Other Commitments [Line Items]
Working interest ownership percentage	56.70%			56.70%		33.30%	70.00%
International Brotherhood of Electrical Workers [Member]
Other Commitments [Line Items]
Percentage of employees belonging to unions	70.00%			70.00%
Number of collective bargaining agreements | agreement				3
Expiration date of collective bargaining agreements				Jun. 30, 2017
Hotel Employees and Restaurant Employees [Member]
Other Commitments [Line Items]
Number of collective bargaining agreements | agreement				1
Expiration date of collective bargaining agreements				Jun. 30, 2016