Statements of convertible preferred stock and preferred units, and stockholders' and members' equity (deficit) (Parenthetical) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)
Unrealized gain on available-for-sale securities, income tax expense	$ 0
Series B Convertible Preferred Stock [Member]
Issuance of Stock, transaction costs	187
Series D Convertible Preferred Stock [Member]
Issuance of Stock, transaction costs	2,502
Common Stock [Member]
Issuance of Stock, transaction costs	$ 14,206

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (e,f)
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580

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Period Type:	duration