Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Schedule of operations by geographic segment
Subtotal	$ 2,217	$ 1,295	$ 6,905	$ 4,669
Net sales	44,250	40,216	122,157	123,340
Segment net income (loss)	151	1,386	(917)	4,898
Depreciation and amortization	3,264	1,525	6,674	4,301
Total assets	235,832	181,027	235,832	181,027	183,849
Subtotal [Member]
Schedule of operations by geographic segment
Subtotal	46,467	41,511	129,062	128,009
Eliminations [Member]
Schedule of operations by geographic segment
Subtotal	(2,217)	(1,295)	(6,905)	(4,669)
Mobile communication [Member] | United States [Member]
Schedule of operations by geographic segment
Subtotal	22,926	21,569	65,567	59,243
Mobile communication [Member] | Canada [Member]
Schedule of operations by geographic segment
Subtotal	198	108	478	391
Mobile communication [Member] | Europe [Member]
Schedule of operations by geographic segment
Subtotal	5,335	4,803	16,877	13,312
Mobile communication [Member] | Other geographic areas [Member]
Schedule of operations by geographic segment
Subtotal	7,736	2,533	11,911	6,226
Guidance and stabilization [Member] | United States [Member]
Schedule of operations by geographic segment
Subtotal	2,169	2,026	6,867	4,889
Guidance and stabilization [Member] | Canada [Member]
Schedule of operations by geographic segment
Subtotal	2,160	3,700	7,681	11,583
Guidance and stabilization [Member] | Europe [Member]
Schedule of operations by geographic segment
Subtotal	1,247	1,437	3,217	5,895
Guidance and stabilization [Member] | Other geographic areas [Member]
Schedule of operations by geographic segment
Subtotal	2,479	4,040	9,559	21,801
Americas [Member]
Schedule of operations by geographic segment
Subtotal	941	746	3,893	3,286
Net sales	32,022	33,763	95,383	106,301
Segment net income (loss)	(1,308)	1,687	(1,869)	5,302
Depreciation and amortization	1,143	1,117	3,403	3,391
Total assets	116,591	132,415	116,591	132,415
Americas [Member] | Subtotal [Member]
Schedule of operations by geographic segment
Subtotal	32,963	34,509	99,276	109,587
Americas [Member] | Eliminations [Member]
Schedule of operations by geographic segment
Subtotal	(941)	(746)	(3,893)	(3,286)
Americas [Member] | Mobile communication [Member] | United States [Member]
Schedule of operations by geographic segment
Subtotal	22,528	21,270	64,434	58,767
Americas [Member] | Mobile communication [Member] | Canada [Member]
Schedule of operations by geographic segment
Subtotal	180	108	427	391
Americas [Member] | Mobile communication [Member] | Europe [Member]
Schedule of operations by geographic segment
Subtotal	79	181	292	409
Americas [Member] | Mobile communication [Member] | Other geographic areas [Member]
Schedule of operations by geographic segment
Subtotal	1,180	1,001	2,906	2,566
Americas [Member] | Guidance and stabilization [Member] | United States [Member]
Schedule of operations by geographic segment
Subtotal	2,169	2,026	6,867	4,889
Americas [Member] | Guidance and stabilization [Member] | Canada [Member]
Schedule of operations by geographic segment
Subtotal	2,160	3,700	7,681	11,583
Americas [Member] | Guidance and stabilization [Member] | Europe [Member]
Schedule of operations by geographic segment
Subtotal	1,247	1,437	3,217	5,895
Americas [Member] | Guidance and stabilization [Member] | Other geographic areas [Member]
Schedule of operations by geographic segment
Subtotal	2,479	4,040	9,559	21,801
Europe and Asia [Member]
Schedule of operations by geographic segment
Subtotal	1,276	549	3,012	1,383
Net sales	12,228	6,453	26,774	17,039
Segment net income (loss)	1,459	(301)	952	(404)
Depreciation and amortization	2,121	408	3,271	910
Total assets	119,241	48,612	119,241	48,612
Europe and Asia [Member] | Subtotal [Member]
Schedule of operations by geographic segment
Subtotal	13,504	7,002	29,786	18,422
Europe and Asia [Member] | Eliminations [Member]
Schedule of operations by geographic segment
Subtotal	(1,276)	(549)	(3,012)	(1,383)
Europe and Asia [Member] | Mobile communication [Member] | United States [Member]
Schedule of operations by geographic segment
Subtotal	398	299	1,133	476
Europe and Asia [Member] | Mobile communication [Member] | Canada [Member]
Schedule of operations by geographic segment
Subtotal	18	0	51	0
Europe and Asia [Member] | Mobile communication [Member] | Europe [Member]
Schedule of operations by geographic segment
Subtotal	5,256	4,622	16,585	12,903
Europe and Asia [Member] | Mobile communication [Member] | Other geographic areas [Member]
Schedule of operations by geographic segment
Subtotal	6,556	1,532	9,005	3,660
Europe and Asia [Member] | Guidance and stabilization [Member] | United States [Member]
Schedule of operations by geographic segment
Subtotal	0	0	0	0
Europe and Asia [Member] | Guidance and stabilization [Member] | Canada [Member]
Schedule of operations by geographic segment
Subtotal	0	0	0	0
Europe and Asia [Member] | Guidance and stabilization [Member] | Europe [Member]
Schedule of operations by geographic segment
Subtotal	0	0	0	0
Europe and Asia [Member] | Guidance and stabilization [Member] | Other geographic areas [Member]
Schedule of operations by geographic segment
Subtotal	$ 0	$ 0	$ 0	$ 0