Common Stock (Details)	12 Months Ended	35 Months Ended
	Dec. 31, 2016 Vote $ / shares shares	Dec. 31, 2016 $ / shares shares	Dec. 31, 2015 $ / shares shares	Oct. 31, 2015 shares	Dec. 31, 2014 $ / shares shares
Class of Stock [Line Items]
Common Stock, Shares Authorized	120,000,000	120,000,000	120,000,000
Common stock, par value (in dollars per share) | $ / shares	$ 0.001	$ 0.001	$ 0.001		$ 0.001
Number of votes entitled for each share of common stock | Vote	1
Dividends declared | $ / shares		0
Dividends paid | $ / shares		$ 0
Shares available for future issuance (in shares)	5,394,249	5,394,249			4,723,719
2015 Stock Option Plan
Class of Stock [Line Items]
Shares available for future issuance (in shares)				1,311,812
Vesting of restricted stock awards | Founder Awards
Class of Stock [Line Items]
Shares available for future issuance (in shares)	628,679	628,679			853,680
Vesting of restricted stock awards | 2014 Stock Option and Stock Plan
Class of Stock [Line Items]
Shares available for future issuance (in shares)	539,305	539,305			964,581
Exercise of stock options
Class of Stock [Line Items]
Shares available for future issuance (in shares)	1,871,237	1,871,237			1,022,617
Issuance under share based compensation plans
Class of Stock [Line Items]
Shares available for future issuance (in shares)	529,854	529,854			262,362
Issuance under share based compensation plans | 2015 Stock Option Plan
Class of Stock [Line Items]
Shares available for future issuance (in shares)	1,825,174	1,825,174			1,620,479