Common Stock, Preferred Stock and Stockholders' Equity - Shares of Common Stock Reserved for Future Issuance (Detail) shares in Thousands	Jun. 30, 2019 shares
Class Of Stock [Line Items]
Common stock reserved for future issuance	4,958,676
Employee Stock Purchase Plan 2013 [Member]
Class Of Stock [Line Items]
Common stock reserved for future issuance	128,571
Equity and Incentive Plan 2013 [Member]
Class Of Stock [Line Items]
Common stock reserved for future issuance	1,244,754
Stock Options Issued and Outstanding [Member]
Class Of Stock [Line Items]
Common stock reserved for future issuance	3,585,351