Property, Plant and Equipment - Summary of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,068,764	$ 1,015,808
Less: accumulated depreciation	(689,903)	(620,967)
Property and equipment, net	378,861	394,841
Land, buildings and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	9,391	9,187
Wireless communication systems
Property, Plant and Equipment [Line Items]
Property and equipment, gross	811,344	785,548
Furniture, equipment, vehicles and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	196,215	176,267
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 51,814	$ 44,806

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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