Number of shares authorized for issuance under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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

Stock-Based Compensation (Narrative) (Details) - shares shares in Millions	May 31, 2020	Sep. 30, 2015
2015 Plan
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Line Items]
Shares available for issuance (in shares)		7.6
Prior Plans
Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Line Items]
Shares available for issuance (in shares)	1.2