Earnings (Loss) Per Common Share (Diluted Net Income (Loss) Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Common Stock - Class A [Member]
Numerator [Abstract]
Undistributed income (loss) allocable to common stockholders for basic computation	$ 2,967	$ (14,330)	$ 3,934	$ (32,048)
Reallocation of undistributed earnings (loss) as a result of conversion of Class B to Class A shares	281	(1,297)	370	(2,848)
Reallocation of undistributed earnings as a result of conversion of dilutive securities	189	0	304	0
Effect of derivative instruments that may be settled in cash or shares	(3,834)	0	(6,501)	0
Effect of share based compensation that may be settled in cash or shares	(39)	0	(62)	0
Undistributed net income (loss) adjusted for allocation of undistributed earnings (loss) and effect of contracts that may be settled in cash or shares	$ (436)	$ (15,627)	$ (1,955)	$ (34,896)
Denominator [Abstract]
Number of shares used in basic computation	33,308	34,887	33,502	35,548
Conversion of Class B to Class A common shares outstanding	3,155	3,159	3,155	3,159
Effect of derivative instruments that may be settled in cash or shares	611	0	744	0
Effect of share based compensation that may be settled in cash or shares	26	0	26	0
Number of shares used in per share computation	37,100	38,046	37,427	38,707
Diluted net loss attributable to GCI common stockholders per common share	$ (0.01)	$ (0.41)	$ (0.05)	$ (0.90)
Common Stock - Class B [Member]
Numerator [Abstract]
Undistributed income (loss) allocable to common stockholders for basic computation	$ 281	$ (1,297)	$ 370	$ (2,848)
Reallocation of undistributed earnings (loss) as a result of conversion of Class B to Class A shares	0	0	0	0
Reallocation of undistributed earnings as a result of conversion of dilutive securities	(319)	0	(536)	0
Effect of derivative instruments that may be settled in cash or shares	0	0	0	0
Effect of share based compensation that may be settled in cash or shares	0	0	0	0
Undistributed net income (loss) adjusted for allocation of undistributed earnings (loss) and effect of contracts that may be settled in cash or shares	$ (38)	$ (1,297)	$ (166)	$ (2,848)
Denominator [Abstract]
Number of shares used in basic computation	3,155	3,159	3,155	3,159
Conversion of Class B to Class A common shares outstanding	0	0	0	0
Effect of derivative instruments that may be settled in cash or shares	0	0	0	0
Effect of share based compensation that may be settled in cash or shares	0	0	0	0
Number of shares used in per share computation	3,155	3,159	3,155	3,159
Diluted net loss attributable to GCI common stockholders per common share	$ (0.01)	$ (0.41)	$ (0.05)	$ (0.90)