Goodwill and Intangible Assets, Net - Finite-Lived Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 61,105			$ 61,105		$ 55,170
Accumulated Amortization	(30,946)			(30,946)		(26,621)
Net	30,159			30,159		28,549
Finite-lived intangible assets, fully amortized, gross	6,000			6,000		10,200
Amortization expense	1,769		$ 1,572	5,160	$ 4,681
Cost of sales
Finite-Lived Intangible Assets, Net [Abstract]
Amortization expense	54		21	128	63
Selling, general and administrative expenses
Finite-Lived Intangible Assets, Net [Abstract]
Amortization expense	1,715		$ 1,551	5,032	$ 4,618
Distribution rights
Finite-Lived Intangible Assets, Net [Abstract]
Gross	340			340		302
Accumulated Amortization	(155)			(155)		(119)
Net	185			185		183
Patents
Finite-Lived Intangible Assets, Net [Abstract]
Gross	12,593			12,593		12,038
Accumulated Amortization	(4,996)			(4,996)		(4,775)
Net	7,597			7,597		7,263
Trademarks and trade names (2)
Finite-Lived Intangible Assets, Net [Abstract]
Gross	2,786			2,786		2,400
Accumulated Amortization	(1,518)			(1,518)		(1,310)
Net	1,268			1,268		1,090
Developed and core technology
Finite-Lived Intangible Assets, Net [Abstract]
Gross	12,560			12,560		12,585
Accumulated Amortization	(5,567)			(5,567)		(4,068)
Net	6,993			6,993		8,517
Capitalized software development costs
Finite-Lived Intangible Assets, Net [Abstract]
Gross	142			142		142
Accumulated Amortization	(59)			(59)		(5)
Net	83			83		137
Customer relationships (2)
Finite-Lived Intangible Assets, Net [Abstract]
Gross	32,534			32,534		27,703
Accumulated Amortization	(18,613)			(18,613)		(16,344)
Net	13,921			13,921		11,359
Order backlog (2)
Finite-Lived Intangible Assets, Net [Abstract]
Gross	150			150		0
Accumulated Amortization	(38)			(38)		0
Net	112			112		$ 0
Residential Control Systems, Inc | Customer relationships (2)
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets	5,000	$ 5,000		5,000
Estimated lives, finite-lived intangible asset		10 years
Residential Control Systems, Inc | Order backlog (2)
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets	150	$ 200		150
Estimated lives, finite-lived intangible asset		1 year
Residential Control Systems, Inc | Trade name
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets	$ 400	$ 400		$ 400
Estimated lives, finite-lived intangible asset		8 years