Stock Based Compensation Activity [Line Items]

No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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No definition available.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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No definition available.

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- Definition

Weighted average price of options that were either forfeited or expired.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Stock-based Compensation Assumptions Used in Black-Scholes Stock Appreciation Rights Valuation Model (Details) - $ / shares	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Employee Stock Option
Stock Based Compensation Activity [Line Items]
Weighted Average SAR Price, Forfeited or expired	$ 38.62
Expected life of SAR (years)	6 years 183 days		6 years 146 days
Risk-free interest rate, minimum	2.80%	1.23%	1.64%
Risk-free interest rate, maximum	2.80%	1.93%	1.70%
Expected volatility of the Company's stock	23.70%	24.60%	36.00%
Expected dividend yield on the Company's stock	2.78%	2.21%	2.11%
Employee Stock Option \| Minimum
Stock Based Compensation Activity [Line Items]
Expected life of SAR (years)		4 years 272 days
Employee Stock Option \| Maximum
Stock Based Compensation Activity [Line Items]
Expected life of SAR (years)		6 years 182 days
Stock Appreciation Rights (SARs)
Stock Based Compensation Activity [Line Items]
Weighted Average SAR Price, Forfeited or expired	$ 26.09
Risk-free interest rate, minimum	2.29%
Risk-free interest rate, maximum	2.94%
Expected volatility of the Company's stock	23.70%
Expected dividend yield on the Company's stock	2.78%
Stock Appreciation Rights (SARs) \| Minimum
Stock Based Compensation Activity [Line Items]
Expected life of SAR (years)	146 days
Stock Appreciation Rights (SARs) \| Maximum
Stock Based Compensation Activity [Line Items]
Expected life of SAR (years)	5 years 37 days