Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 241,344	$ 258,573	$ 247,528	$ 231,089	$ 228,791	$ 240,725	$ 224,399	$ 216,283	$ 978,534	$ 910,198	$ 811,648
Operating income	20,589	45,549	39,257	816	25,547	49,336	38,414	30,265	106,211	143,562	112,862
Net income (loss)	2,588	19,802	(14,701)	(17,721)	5,796	25,847	16,840	10,761	(10,032)	59,244	31,727
Net income (loss) attributable to GCI, Inc.	$ 2,759	$ 19,918	$ (14,622)	$ (18,246)	$ (9,425)	$ 9,915	$ 5,927	$ 1,140	$ (10,191)	$ 7,557	$ 9,406