Employee Benefit Plans - Equity Incentive Plan (Details) shares in Millions	Sep. 30, 2020 shares
Equity incentive plan 2015
Share-Based Compensation Plans
Number of shares available for future issuance (in shares)	12.4
Employee stock purchase plan 2008
Share-Based Compensation Plans
Number of shares available for future issuance (in shares)	11.5

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant