Summary of Financial Information of Laser Quantum - Income Statement (Details) (Laser Quantum, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Laser Quantum
Schedule Of Financial Statements Information [Line Items]
Sales	$ 23,013	$ 16,269	$ 13,039
Income from operations	7,434	4,720	3,592
Net income	$ 6,627	$ 3,745	$ 2,215