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		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Operating revenues	$ 58,229	$ 56,703	$ 173,779	$ 171,970
Total operating expenses	52,466	53,031	154,385	157,814
Operating income	5,763	3,672	19,394	14,156
Income before income tax expense	2,579	(138)	9,356	(5,140)
Net income attributable to Alaska Communications	$ 1,817	$ 320	$ 7,360	$ (3,154)
Basic (in dollars per share)	$ 0.03	$ 0.01	$ 0.14	$ (0.06)
Diluted (in dollars per share)	$ 0.03	$ 0.01	$ 0.14	$ (0.06)
Deferred income taxes	$ 820		$ 820		$ 3,394
Other assets	19,330		19,330		11,415
Total assets	449,969		449,969		442,786
Deferred income taxes	2,233		2,233		596
Total liabilities	281,931		281,931		288,276
Retained earnings	8,719		8,719		(3,579)
Total liabilities and stockholders' equity	449,969		449,969		$ 442,786
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Operating revenues
Total operating expenses	676		772
Operating income	(676)		(772)
Income before income tax expense	(676)		(772)
Net income attributable to Alaska Communications	$ (484)		$ (553)
Basic (in dollars per share)	$ 0		$ (0.01)
Diluted (in dollars per share)	$ (0.01)		$ (0.01)
Deferred income taxes	$ 1,460		$ 1,460
Other assets	(7,670)		(7,670)
Total assets	(6,210)		(6,210)
Deferred income taxes	(719)		(719)
Total liabilities	(719)		(719)
Retained earnings	(5,491)		(5,491)
Total liabilities and stockholders' equity	(6,210)		(6,210)
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Operating revenues	58,229		173,779
Total operating expenses	53,142		155,157
Operating income	5,087		18,622
Income before income tax expense	1,903		8,584
Net income attributable to Alaska Communications	$ 1,333		$ 6,807
Basic (in dollars per share)	$ 0.03		$ 0.13
Diluted (in dollars per share)	$ 0.02		$ 0.13
Deferred income taxes	$ 2,280		$ 2,280
Other assets	11,660		11,660
Total assets	443,759		443,759
Deferred income taxes	1,514		1,514
Total liabilities	281,212		281,212
Retained earnings	3,228		3,228
Total liabilities and stockholders' equity	$ 443,759		$ 443,759