Equity Award Plan Activities - Additional Information (Details) - $ / shares		3 Months Ended
	Jan. 01, 2018	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized for issuance (in shares)		2,211,000
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value of options granted (in dollars per share)		$ 67.09
2014 Equity Incentive Plan | Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized for issuance (in shares)	2,211,176
Percent of shares outstanding to increase number of shares available for grant and issuance	3.00%
Maximum increase of number of shares available for issuance (in shares)	12,500,000
Common stock reserved for issuance (in shares)		23,800,000
2014 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized for issuance (in shares)	737,058
Percent of shares outstanding to increase number of shares available for grant and issuance	1.00%
Maximum increase of number of shares available for issuance (in shares)	2,500,000
Common stock reserved for issuance (in shares)		2,615,207
Shares issued during period (in shares)		108,890