Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Jun. 25, 2014	Jun. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jun. 05, 2014
Subsidiary, Sale of Stock [Line Items]
Proceeds from issuance of common stock			$ 1,320	$ 38,018
Payments of Stock Issuance Costs				1,920
Allocated Share-based Compensation Expense			$ 12,815	$ 9,280	$ 7,035
Common stock; authorized shares			300,000,000	300,000,000		300,000,000
Common stock par value (in dollars per share)			$ 0.0001	$ 0.0001		$ 0.0001
Preferred stock, shares authorized			20,000,000	20,000,000		20,000,000
Preferred stock, par value (in dollars per share)			$ 0.0001	$ 0.0001		$ 0.0001
Preferred stock, shares issued			0	0
Preferred stock, shares outstanding			0	0
Employee Consultant And Directors Stock Options
Subsidiary, Sale of Stock [Line Items]
Allocated Share-based Compensation Expense			$ 7,900	$ 6,700	$ 5,900
IPO [Member]
Subsidiary, Sale of Stock [Line Items]
Stock Issued During Period, Shares, New Issues	5,840,000
Share Price (in Dollars per share)	$ 7.00
Proceeds from issuance of common stock	$ 40,900
Payments of Stock Issuance Costs	$ 6,200
Proceeds from Issuance Initial Public Offering, Net of Issuance Costs (in Dollars)		$ 34,700
IPO [Member] | Underwriter
Subsidiary, Sale of Stock [Line Items]
Stock Issued During Period, Shares, New Issues	1,200,000