Employee service share-based compensation, cash paid primarily to taxing authorities from exercise of incentive shares

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- Definition

Performance shares distributed in cash, primarily for tax withholding

+ References

No definition available.

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- Definition

Restricted stock awarded

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No definition available.

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- Definition

Restricted stock units awarded.

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- Definition

Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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 (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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 (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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.

+ References

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=116856206&loc=d3e5070-113901

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

No definition available.

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Stock-Based Compensation (Supplemental Incentive Share Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Incentive Shares Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period	2,259,000
Unvested shares outstanding	5,916,000	6,325,000
Share-based compensation arrangement by share-based payment award, number of shares available for grant	7,000,000.0
Total fair value of shares earned/vested	$ 164	$ 145	$ 20
Share award distributed in cash, primarily for tax withholding	$ 81	$ 73	$ 9
Performance Shares [Member] \| 2016 Performance Share Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		2016 - 2018
Percent payout		97.00%
Shares vested in period		1,819,000
Performance shares distributed in cash, primarily for tax withholding		795,000
Performance Shares [Member] \| 2017 Performance Share Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	2017 - 2019
Percent payout	107.00%
Shares vested in period	2,008,000
Performance shares distributed in cash, primarily for tax withholding	883,000
Performance Shares [Member] \| 2018 Performance Share Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent payout	100.00%
Unvested shares outstanding	1,538,000
Performance Shares [Member] \| 2019 Performance Share Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares outstanding	1,381,000
Performance Shares [Member] \| 2020 Performance Share Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares outstanding	1,592,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period	173,000
Unvested shares outstanding	1,405,000
Common shares issued	100,000
Shares withheld for income taxes	73,000
Restricted Stock For Non Management Directors Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awarded	19,000
Restricted stock units awarded	2,000
Share-based compensation arrangement by share-based payment award, number of shares available for grant	119,000