Note 2 - Revenue Recognition - Effect of Adoption of ASC 606 on the Company's Statement of Comprehensive Income and Balance Sheet (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Operating revenues	$ 59,578	$ 58,536	$ 115,550	$ 115,267
Total operating expenses	51,290	52,780	101,919	104,783
Operating income	8,288	5,756	13,631	10,484
Income before income tax expense	4,820	(3,462)	6,777	(5,002)
Net income attributable to Alaska Communications	$ 3,442	$ (2,798)	$ 5,543	$ (3,474)
Net income per share attributable to Alaska
Basic (in dollars per share)	$ 0.06	$ (0.05)	$ 0.10	$ (0.07)
Diluted (in dollars per share)	$ 0.06	$ (0.05)	$ 0.10	$ (0.07)
Operating revenues	$ 59,578	$ 58,536	$ 115,550	$ 115,267
Total operating expenses	51,290	52,780	101,919	104,783
Operating income	8,288	5,756	13,631	10,484
Income before income tax expense	4,820	(3,462)	6,777	(5,002)
Net income attributable to Alaska Communications	3,442	$ (2,798)	5,543	$ (3,474)
Deferred income taxes	1,311		1,311		$ 3,394
Other assets	18,828		18,828		11,415
Total assets	452,464		452,464		442,786
Deferred income taxes	1,972		1,972		596
Total liabilities	286,818		286,818		288,276
Retained earnings (accumulated deficit)	6,902		6,902		$ (3,579)
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Operating revenues
Total operating expenses	442		96
Operating income	(442)		(96)
Income before income tax expense	(442)		(96)
Net income attributable to Alaska Communications	$ (312)		$ (69)
Net income per share attributable to Alaska
Basic (in dollars per share)	$ 0
Diluted (in dollars per share)	$ 0		$ 0
Operating revenues
Total operating expenses	442		96
Operating income	(442)		(96)
Income before income tax expense	(442)		(96)
Net income attributable to Alaska Communications	(312)		(69)
Deferred income taxes	1,331		1,331
Other assets	(6,994)		(6,994)
Total assets	(5,663)		(5,663)
Deferred income taxes	(656)		(656)
Total liabilities	(656)		(656)
Retained earnings (accumulated deficit)	(5,007)		(5,007)
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Operating revenues	59,578		115,550
Total operating expenses	51,732		102,015
Operating income	7,846		13,535
Income before income tax expense	4,378		6,681
Net income attributable to Alaska Communications	$ 3,130		$ 5,474
Net income per share attributable to Alaska
Basic (in dollars per share)	$ 0.06
Diluted (in dollars per share)	$ 0.06		$ 0.10
Operating revenues	$ 59,578		$ 115,550
Total operating expenses	51,732		102,015
Operating income	7,846		13,535
Income before income tax expense	4,378		6,681
Net income attributable to Alaska Communications	3,130		5,474
Deferred income taxes	2,642		2,642
Other assets	11,834		11,834
Total assets	446,801		446,801
Deferred income taxes	1,316		1,316
Total liabilities	286,162		286,162
Retained earnings (accumulated deficit)	$ 1,895		$ 1,895