Segment Reporting and Geographic Information (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) segment	Sep. 30, 2014 USD ($)	Dec. 31, 2014
Segment Reporting Information [Line Items]
Number of business segments | segment			2
Revenue	$ 37,275	$ 43,170	$ 118,762	$ 128,612
Network Integration [Member]
Segment Reporting Information [Line Items]
Revenue	14,343	21,237	49,126	62,644
Network Integration [Member] | Major Customer, One [Member]
Segment Reporting Information [Line Items]
Revenue	$ 7,500	$ 11,000	$ 24,400	$ 33,800
Network Integration [Member] | Major Customer, One [Member] | Customer Concentration Risk [Member] | Revenue [Member]
Segment Reporting Information [Line Items]
Concentration percentage	20.00%	25.00%	21.00%	26.00%
Network Integration [Member] | Major Customer, One [Member] | Customer Concentration Risk [Member] | Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Concentration percentage			7.00%		5.00%
Network Integration [Member] | Major Customer, Two [Member]
Segment Reporting Information [Line Items]
Revenue	$ 4,800	$ 6,100	$ 16,500	$ 20,200
Network Integration [Member] | Major Customer, Two [Member] | Customer Concentration Risk [Member] | Revenue [Member]
Segment Reporting Information [Line Items]
Concentration percentage	13.00%	14.00%	14.00%	16.00%
Network Integration [Member] | Major Customer, Two [Member] | Customer Concentration Risk [Member] | Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Concentration percentage			23.00%		29.00%
Network Equipment [Member]
Segment Reporting Information [Line Items]
Revenue	$ 22,974	$ 21,979	$ 69,787	$ 66,131