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Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 342,401		$ 342,401		$ 327,810	$ 344,784
Depreciation	19,700	$ 15,100	51,600	$ 41,100
Non-communications
Property, Plant and Equipment [Line Items]
Property and equipment, gross	244,777		244,777			231,995
Accumulated depreciation	(147,266)		(147,266)			(123,003)
Property and equipment, net	97,511		97,511			108,992
Non-communications | Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	161,420		$ 161,420			137,705
Non-communications | Computer equipment and software | Minimum
Property, Plant and Equipment [Line Items]
Useful life			1 year
Non-communications | Computer equipment and software | Maximum
Property, Plant and Equipment [Line Items]
Useful life			5 years
Non-communications | Building and building improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	38,621		$ 38,621			50,138
Non-communications | Building and building improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful life			5 years
Non-communications | Building and building improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful life			48 years
Non-communications | Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	24,354		$ 24,354			22,796
Non-communications | Office furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life			1 year
Non-communications | Office furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life			10 years
Non-communications | Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	10,193		$ 10,193			9,327
Non-communications | Leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful life			1 year
Non-communications | Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful life			15 years
Non-communications | Transportation equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,049		$ 5,049			5,123
Non-communications | Transportation equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life			5 years
Non-communications | Transportation equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life			10 years
Non-communications | Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,400		$ 1,400			3,328
Non-communications | Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,740		3,740			3,578
Communications
Property, Plant and Equipment [Line Items]
Property and equipment, gross	308,119		308,119			273,865
Accumulated depreciation	(63,229)		(63,229)			(38,073)
Property and equipment, net	244,890		244,890			235,792
Communications | Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,443		$ 5,443			4,943
Communications | Computer equipment and software | Minimum
Property, Plant and Equipment [Line Items]
Useful life			1 year
Communications | Computer equipment and software | Maximum
Property, Plant and Equipment [Line Items]
Useful life			5 years
Communications | Transportation equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	6,728		$ 6,728			6,580
Communications | Transportation equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life			4 years
Communications | Transportation equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life			10 years
Communications | Network plant and fiber
Property, Plant and Equipment [Line Items]
Property and equipment, gross	246,971		$ 246,971			215,787
Communications | Network plant and fiber | Minimum
Property, Plant and Equipment [Line Items]
Useful life			4 years
Communications | Network plant and fiber | Maximum
Property, Plant and Equipment [Line Items]
Useful life			15 years
Communications | Customer located property
Property, Plant and Equipment [Line Items]
Property and equipment, gross	25,966		$ 25,966			21,234
Communications | Customer located property | Minimum
Property, Plant and Equipment [Line Items]
Useful life			3 years
Communications | Customer located property | Maximum
Property, Plant and Equipment [Line Items]
Useful life			4 years
Communications | Central office
Property, Plant and Equipment [Line Items]
Property and equipment, gross	17,499		$ 17,499			15,688
Communications | Central office | Minimum
Property, Plant and Equipment [Line Items]
Useful life			5 years
Communications | Central office | Maximum
Property, Plant and Equipment [Line Items]
Useful life			15 years
Communications | Other
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,391		$ 3,391			3,219
Communications | Other | Minimum
Property, Plant and Equipment [Line Items]
Useful life			1 year
Communications | Other | Maximum
Property, Plant and Equipment [Line Items]
Useful life			39 years
Communications | Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	70		$ 70			70
Communications | Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,051		$ 2,051			$ 6,344

X

- Definition

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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