Stockholders' Equity - Common Stock Reserved for Future Issuance (Details) shares in Thousands	Mar. 31, 2020 shares
Class of Stock
Common stock reserved for future issuance (in shares)	20,044
Stock options
Class of Stock
Common stock reserved for future issuance (in shares)	2,557
Restricted stock units
Class of Stock
Common stock reserved for future issuance (in shares)	2,962
ESPP
Class of Stock
Common stock reserved for future issuance (in shares)	2,700
2014 Plan
Class of Stock
Common stock reserved for future issuance (in shares)	11,825