Property, Plant and Equipment - Schedule of Carrying Value of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 6,851,727	$ 6,751,076
Less accumulated depreciation	(4,179,378)	(4,081,039)
Net property, plant and equipment	$ 2,672,349	2,670,037
Land
Property Plant And Equipment [Line Items]
Depreciable Lives	Indefinite
Property, plant and equipment, gross	$ 28,385	26,833
Building and Improvements
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 320,061	318,967
Building and Improvements | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	3 years
Building and Improvements | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	40 years
Real Property Interests
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 20,313	12,265
Real Property Interests | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	50 years
Real Property Interests | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	99 years
Poles
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 234,785	234,393
Poles | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	13 years
Poles | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	40 years
Fiber
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 2,264,718	2,243,822
Fiber | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	7 years
Fiber | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	40 years
Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 134,461	130,945
Equipment | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	5 years
Equipment | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	7 years
Copper
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 3,553,467	3,538,566
Copper | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	7 years
Copper | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	40 years
Conduit
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 90,531	90,540
Conduit | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	13 years
Conduit | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	47 years
Tower assets
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 45,523	4,307
Tower assets | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	20 years
Tower assets | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	49 years
Capital Lease Assets
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 90,279	89,723
Other assets
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 5,299	5,299
Other assets | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	15 years
Other assets | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	20 years
Corporate assets
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 2,612	2,731
Corporate assets | Minimum
Property Plant And Equipment [Line Items]
Depreciable Lives	3 years
Corporate assets | Maximum
Property Plant And Equipment [Line Items]
Depreciable Lives	7 years
Construction in progress
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 61,293	$ 52,685