Deferred Compensation Arrangement With Individual, Vesting, Percentage

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Award Vesting Rights, Performance Period

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- Definition

Significant Accounting Policies [Line Items]

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

The per share price that the individual must pay to acquire shares under the deferred compensation arrangement.

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- Definition

The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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-Publisher FASB
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Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Amount of cost (reversal of cost) for pension and other postretirement benefits.

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No definition available.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

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

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SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions				1 Months Ended	12 Months Ended
	Dec. 01, 2018	Dec. 01, 2017	Dec. 01, 2016	Nov. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Oct. 01, 2019	Nov. 30, 2017	Nov. 30, 2016
Significant Accounting Policies [Line Items]
Compensation costs recognized					$ 18	$ 20	$ 19
Impact of convertible notes (in shares)					900,000	900,000	500,000
Non-service cost components of the net periodic pension and OPEB					$ (37)	$ (31)	$ 11
Convertible Notes \| 7.875% convertible notes due 2026
Significant Accounting Policies [Line Items]
Stated interest rate					7.875%
Executive Officer
Significant Accounting Policies [Line Items]
Number of shares issuable per performance share unit (in shares)	1								1	1
Restricted Stock Units (RSUs)
Significant Accounting Policies [Line Items]
Shares granted in period (in shares)					500,000	400,000	600,000
Vesting term					3 years
Restricted Stock Units (RSUs) \| Executive Officer
Significant Accounting Policies [Line Items]
Exercise price (usd per share)		$ 24.79	$ 12.77
Shares granted in period (in shares)		300,000	500,000	400,000
Vesting term	3 years	3 years	3 years
Performance Shares
Significant Accounting Policies [Line Items]
Compensation costs recognized					$ 10	$ 14	$ 14
Performance Shares \| Executive Officer
Significant Accounting Policies [Line Items]
Exercise price (usd per share)	$ 16.50	$ 24.79	$ 12.77
Restricted Shares, Restricted Share Units and Performance Share Units
Significant Accounting Policies [Line Items]
Impact of instruments attributable to dilutive effect of share-based payment arrangements (in shares)					2,200,000	2,800,000	1,700,000
Performance period of October 1, 2018 to September 30, 2021 \| Performance Shares \| Executive Officer
Significant Accounting Policies [Line Items]
Performance period	3 years
Shares authorized for grant (in shares)				500,000
Performance period of October 1, 2018 to September 30, 2021 \| Performance Shares \| Executive Officer \| Minimum
Significant Accounting Policies [Line Items]
Performance-based vesting percentage					0.00%
Performance period of October 1, 2018 to September 30, 2021 \| Performance Shares \| Executive Officer \| Maximum
Significant Accounting Policies [Line Items]
Performance-based vesting percentage					200.00%
Performance period of October 1, 2018 to September 30, 2021 \| Performance Shares \| Executive Officer \| Performance Objective One
Significant Accounting Policies [Line Items]
Award vesting rights percentage					50.00%
Performance period of October 1, 2018 to September 30, 2021 \| Performance Shares \| Executive Officer \| Performance Objective Two
Significant Accounting Policies [Line Items]
Award vesting rights percentage					50.00%
Performance period of October 1, 2017 to September 30, 2020 \| Performance Shares \| Executive Officer
Significant Accounting Policies [Line Items]
Performance period		3 years			3 years
Shares authorized for grant (in shares)		300,000
Performance period of October 1, 2017 to September 30, 2020 \| Performance Shares \| Executive Officer \| Minimum
Significant Accounting Policies [Line Items]
Performance-based vesting percentage					0.00%
Performance period of October 1, 2017 to September 30, 2020 \| Performance Shares \| Executive Officer \| Maximum
Significant Accounting Policies [Line Items]
Performance-based vesting percentage					200.00%
Performance period of October 1, 2017 to September 30, 2020 \| Performance Shares \| Executive Officer \| Performance Objective One
Significant Accounting Policies [Line Items]
Award vesting rights percentage					50.00%
Performance period of October 1, 2017 to September 30, 2020 \| Performance Shares \| Executive Officer \| Performance Objective Two
Significant Accounting Policies [Line Items]
Award vesting rights percentage					50.00%
Performance period of October 1, 2016 to September 30, 2019 \| Performance Shares \| Executive Officer
Significant Accounting Policies [Line Items]
Performance period			3 years
Ten Customers \| Customer Concentration Risk \| Sales
Significant Accounting Policies [Line Items]
Concentration risk from significant customers, percentage					77.00%	75.00%	74.00%
Three Customers \| Customer Concentration Risk \| Sales
Significant Accounting Policies [Line Items]
Concentration risk from significant customers, percentage					54.00%	52.00%	49.00%
Three Customers \| Customer Concentration Risk \| Trade Accounts Receivable
Significant Accounting Policies [Line Items]
Concentration risk from significant customers, percentage					26.00%	23.00%
Accounting Standards Update 2017-07
Significant Accounting Policies [Line Items]
Non-service cost components of the net periodic pension and OPEB						$ (25)	$ 11
Forecast \| Minimum
Significant Accounting Policies [Line Items]
Right-of-use asset								$ 75
Forecast \| Maximum
Significant Accounting Policies [Line Items]
Right-of-use asset								95
Subsequent Event \| Forecast \| Accounting Standards Update 2016-02 \| Minimum
Significant Accounting Policies [Line Items]
Lease liability								75
Subsequent Event \| Forecast \| Accounting Standards Update 2016-02 \| Maximum
Significant Accounting Policies [Line Items]
Lease liability								$ 95