Summary of Financial Information of Laser Quantum - Income Statement (Detail) (Laser Quantum, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Laser Quantum
Schedule Of Financial Statements Information [Line Items]
Sales	$ 16,269	$ 13,039	$ 18,384
Income from operations	4,720	3,592	3,994
Net income	$ 3,745	$ 2,215	$ 4,684