Organization and Description of Business (Details) - USD ($) $ / shares in Units, $ in Millions	Jul. 07, 2015	Jun. 17, 2015
Initial Public Offering
Number of shares issued upon conversion of convertible stock	25,500,000
Convertible Preferred Stock
Initial Public Offering
Number of shares issued upon conversion of convertible stock	25,500,000
Redeemable Common Stock
Initial Public Offering
Number of shares issued upon conversion of convertible stock	113,294
IPO And Over-Allotment Option
Initial Public Offering
Issuance of stock under IPO (in shares)	9,487,500	9,487,500
Price of stock issued (in dollars per share)	$ 19.00	$ 19.00
Proceeds received, net of issuance costs	$ 163.1	$ 163.1
Underwriting discounts and commissions	12.6	12.6
Other offering expenses	$ 4.5	$ 4.5