Quarterly Segment Financial Summary (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Segment Reporting Information [Line Items]
Segment Reporting Information			3
Revenue from unaffiliated customers	$ 45,813	$ 45,244	$ 136,614	$ 123,974
Intersegment revenue	0	0	0	0
Total operating revenue	45,813	45,244	136,614	123,974
Depreciation and amortization	6,869	5,794	19,795	17,155
Operating income	4,557	6,342	14,296	16,010
Interest expense	1,625	2,880	4,635	5,199
Income tax provision (benefit)	1,194	1,355	3,925	4,034
Net income (loss)	1,741	2,133	5,773	6,827
Total assets	268,750	246,926	268,750	246,926	243,986
Property, plant and equipment, net	176,803	152,438	176,803	152,438	153,930
Additions to property, plant and equipment	9,354	5,641	18,910	14,132
Fiber and Data Segment [Member]
Segment Reporting Information [Line Items]
Revenue from unaffiliated customers	15,528	11,368	43,924	33,296
Intersegment revenue	215	219	601	566
Total operating revenue	15,743	11,587	44,525	33,862
Depreciation and amortization	2,638	1,597	7,155	4,739
Operating income	2,445	1,926	7,074	5,333
Interest expense	2	0	2	0
Income tax provision (benefit)	990	780	2,865	2,161
Net income (loss)	1,454	1,146	4,208	3,173
Total assets	109,869	73,858	109,869	73,858
Property, plant and equipment, net	88,157	57,128	88,157	57,128
Additions to property, plant and equipment	6,390	2,988	11,958	7,211
Equipment Segment [Member]
Segment Reporting Information [Line Items]
Revenue from unaffiliated customers	15,001	16,416	45,286	38,586
Intersegment revenue	0	0	0	0
Total operating revenue	15,001	16,416	45,286	38,586
Depreciation and amortization	71	74	213	213
Operating income	890	1,250	2,109	2,454
Interest expense	0	0	0	1
Income tax provision (benefit)	360	506	854	995
Net income (loss)	529	744	1,254	1,458
Total assets	21,213	27,083	21,213	27,083
Property, plant and equipment, net	1,347	1,332	1,347	1,332
Additions to property, plant and equipment	(15)	213	175	306
Telecom Segment [Member]
Segment Reporting Information [Line Items]
Revenue from unaffiliated customers	15,284	17,460	47,404	52,092
Intersegment revenue	465	404	1,319	1,220
Total operating revenue	15,749	17,864	48,723	53,312
Depreciation and amortization	4,146	4,101	12,364	12,137
Operating income	1,377	3,000	5,557	8,600
Interest expense	9	13	31	46
Income tax provision (benefit)	554	1,216	2,246	3,473
Net income (loss)	816	1,787	3,301	5,102
Total assets	120,056	127,163	120,056	127,163
Property, plant and equipment, net	87,237	93,896	87,237	93,896
Additions to property, plant and equipment	2,979	2,440	6,777	6,615
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenue from unaffiliated customers	0	0	0	0
Intersegment revenue	(680)	(623)	(1,920)	(1,786)
Total operating revenue	(680)	(623)	(1,920)	(1,786)
Depreciation and amortization	14	22	63	66
Operating income	(155)	166	(444)	(377)
Interest expense	1,614	2,867	4,602	5,152
Income tax provision (benefit)	(710)	(1,147)	(2,040)	(2,595)
Net income (loss)	(1,058)	(1,544)	(2,990)	(2,906)
Total assets	17,613	18,822	17,613	18,822
Property, plant and equipment, net	62	82	62	82
Additions to property, plant and equipment	$ 0	$ 0	$ 0	$ 0