Business Combination - Pro forma results (Details) - Tunable Laser Product Lines From EMCORE Corporation [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Business Acquisition Pro Forma Information Nonrecurring Adjustment [Line Items]
Revenue	$ 99,145	$ 81,384
Net income (loss)	$ 2,310	$ 191
Basic net income (loss) per share	$ 0.06	$ 0.01
Diluted net income (loss) per share	$ 0.05	$ 0.01

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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