Segment Reporting - Selected Financial Data for Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
External revenue
Service revenue and other	$ 59,691	$ 53,134
Operating expenses
Cost of services	23,283	20,317
Selling, general and administrative	20,153	22,096
Restructuring expense	618	0
Depreciation and amortization	13,266	12,085
Total operating expenses	57,320	54,498
Operating income (loss)	2,371	(1,364)
Operating Segments | Broadband
External revenue
Service revenue and other	55,154	49,786
Operating expenses
Selling, general and administrative	10,725	9,704
Restructuring expense	105
Depreciation and amortization	11,761	10,034
Total operating expenses	44,727	39,124
Operating income (loss)	10,427	10,662
Operating Segments | Tower
External revenue
Service revenue and other	4,665	3,730
Operating expenses
Selling, general and administrative	234	526
Restructuring expense	0
Depreciation and amortization	481	470
Total operating expenses	1,963	1,935
Operating income (loss)	2,702	1,795
Intersegment Eliminations
External revenue
Service revenue and other	4,595	4,084
Intersegment Eliminations | Broadband
External revenue
Service revenue and other	2,208	2,533
Intersegment Eliminations | Tower
External revenue
Service revenue and other	2,515	1,933
Intersegment Eliminations | Corporate & Eliminations
External revenue
Service revenue and other	(128)	(382)
Corporate, Non-Segment
Operating expenses
Selling, general and administrative	9,194	11,866
Restructuring expense	513
Depreciation and amortization	1,024	1,581
Total operating expenses	10,630	13,439
Operating income (loss)	(10,758)	(13,821)
Residential & SMB | Operating Segments
External revenue
Service revenue and other	42,930	37,009
Residential & SMB | Operating Segments | Broadband
External revenue
Service revenue and other	42,930	37,009
Residential & SMB | Operating Segments | Tower
External revenue
Service revenue and other	0	0
Commercial Fiber | Operating Segments
External revenue
Service revenue and other	6,385	6,200
Commercial Fiber | Operating Segments | Broadband
External revenue
Service revenue and other	6,385	6,200
Commercial Fiber | Operating Segments | Tower
External revenue
Service revenue and other	0	0
RLEC & Other | Operating Segments
External revenue
Service revenue and other	3,631	4,044
RLEC & Other | Operating Segments | Broadband
External revenue
Service revenue and other	3,631	4,044
RLEC & Other | Operating Segments | Tower
External revenue
Service revenue and other	0	0
Tower lease | Operating Segments
External revenue
Service revenue and other	2,150	1,797
Tower lease | Operating Segments | Broadband
External revenue
Service revenue and other	0	0
Tower lease | Operating Segments | Tower
External revenue
Service revenue and other	2,150	1,797
Service revenue and other | Operating Segments
External revenue
Service revenue and other	55,096	49,050
Service revenue and other | Operating Segments | Broadband
External revenue
Service revenue and other	52,946	47,253
Service revenue and other | Operating Segments | Tower
External revenue
Service revenue and other	2,150	1,797
Cost of services
Operating expenses
Cost of services	23,283	20,317
Cost of services | Operating Segments | Broadband
Operating expenses
Cost of services	22,136	19,386
Cost of services | Operating Segments | Tower
Operating expenses
Cost of services	1,248	939
Cost of services | Corporate, Non-Segment
Operating expenses
Cost of services	$ (101)	$ (8)