Organization and Nature of Business (Detail) (Common stock, USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended	6 Months Ended
	May 31, 2014	Jun. 30, 2014
Initial Public Offering
Shares sold		8,941,250
Shares of common stock issued for conversion of Series A preferred	2,857,143	2,857,143
IPO
Initial Public Offering
Shares sold	8,941,250
Public offering price per share	$ 9.00
Net proceeds from sale of shares in IPO	$ 69.2
Over-allotment option
Initial Public Offering
Shares sold	1,166,250