Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015 Segment State	Mar. 31, 2014		Dec. 31, 2014
Segment Information [Abstract]
Number of reportable segments	3
Non Sprint operations, number of states	4
External revenues [Abstract]
Service revenues	$ 74,526	$ 70,702
Other	9,761	9,750
Total external revenues	84,287	80,452
Internal revenues	0	0
Total operating revenues	84,287	80,452
Operating expenses [Abstract]
Cost of goods and services, exclusive of depreciation and amortization shown separately below	30,691	32,236
Selling, general and administrative, exclusive of depreciation and amortization shown separately below	18,733	17,149
Depreciation and amortization	16,337	15,387
Total operating expenses	65,761	64,772
Operating income (loss)	18,526	15,680
Reconciliation of income from continuing operations from segments to consolidated [Abstract]
Total consolidated operating income	18,526	15,680
Interest expense	(1,915)	(2,048)
Non-operating income (expense), net	534	610
Income before income taxes	17,145	14,242
Assets by segment [Abstract]
Assets	615,506			619,242
Wireless [Member]
Assets by segment [Abstract]
Assets	206,109			218,887
Cable [Member]
Assets by segment [Abstract]
Assets	208,736			201,232
Wireline [Member]
Assets by segment [Abstract]
Assets	95,614			98,081
Other [Member]
Assets by segment [Abstract]
Assets	461,505			446,028
Total Segments [Member]
Assets by segment [Abstract]
Assets	971,964			964,228
Reportable Segments [Member] | Wireless [Member]
External revenues [Abstract]
Service revenues	48,375	47,232
Other	3,030	2,756
Total external revenues	51,405	49,988
Internal revenues	1,104	1,091
Total operating revenues	52,509	51,079
Operating expenses [Abstract]
Cost of goods and services, exclusive of depreciation and amortization shown separately below	16,187	18,657
Selling, general and administrative, exclusive of depreciation and amortization shown separately below	9,052	8,432
Depreciation and amortization	7,831	7,196
Total operating expenses	33,070	34,285
Operating income (loss)	19,439	16,794
Reconciliation of income from continuing operations from segments to consolidated [Abstract]
Total consolidated operating income	19,439	16,794
Reportable Segments [Member] | Cable [Member]
External revenues [Abstract]
Service revenues	21,401	18,874	[1]
Other	1,762	1,580	[1]
Total external revenues	23,163	20,454	[1]
Internal revenues	148	26	[1]
Total operating revenues	23,311	20,480	[1]
Operating expenses [Abstract]
Cost of goods and services, exclusive of depreciation and amortization shown separately below	13,618	12,390	[1]
Selling, general and administrative, exclusive of depreciation and amortization shown separately below	4,892	4,646	[1]
Depreciation and amortization	5,480	5,404	[1]
Total operating expenses	23,990	22,440	[1]
Operating income (loss)	(679)	(1,960)	[1]
Reconciliation of income from continuing operations from segments to consolidated [Abstract]
Total consolidated operating income	(679)	(1,960)	[1]
Reportable Segments [Member] | Wireline [Member]
External revenues [Abstract]
Service revenues	4,750	4,596	[1]
Other	4,969	5,414	[1]
Total external revenues	9,719	10,010	[1]
Internal revenues	5,866	5,765	[1]
Total operating revenues	15,585	15,775	[1]
Operating expenses [Abstract]
Cost of goods and services, exclusive of depreciation and amortization shown separately below	7,334	7,482	[1]
Selling, general and administrative, exclusive of depreciation and amortization shown separately below	1,498	1,244	[1]
Depreciation and amortization	2,924	2,697	[1]
Total operating expenses	11,756	11,423	[1]
Operating income (loss)	3,829	4,352	[1]
Reconciliation of income from continuing operations from segments to consolidated [Abstract]
Total consolidated operating income	3,829	4,352	[1]
Reportable Segments [Member] | Other [Member]
External revenues [Abstract]
Service revenues	0	0
Other	0	0
Total external revenues	0	0
Internal revenues	0	0
Total operating revenues	0	0
Operating expenses [Abstract]
Cost of goods and services, exclusive of depreciation and amortization shown separately below	17	0
Selling, general and administrative, exclusive of depreciation and amortization shown separately below	3,944	3,416
Depreciation and amortization	102	90
Total operating expenses	4,063	3,506
Operating income (loss)	(4,063)	(3,506)
Reconciliation of income from continuing operations from segments to consolidated [Abstract]
Total consolidated operating income	(4,063)	(3,506)
Eliminations [Member]
External revenues [Abstract]
Service revenues	0	0
Other	0	0
Total external revenues	0	0
Internal revenues	(7,118)	(6,882)
Total operating revenues	(7,118)	(6,882)
Operating expenses [Abstract]
Cost of goods and services, exclusive of depreciation and amortization shown separately below	(6,465)	(6,293)
Selling, general and administrative, exclusive of depreciation and amortization shown separately below	(653)	(589)
Depreciation and amortization	0	0
Total operating expenses	(7,118)	(6,882)
Operating income (loss)	0	0
Reconciliation of income from continuing operations from segments to consolidated [Abstract]
Total consolidated operating income	0	0
Assets by segment [Abstract]
Assets	$ (356,458)			$ (344,986)

[1] Prior year figures have been recast to conform to current year presentation.