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Stock Incentive Plans - Stock Appreciation Rights (Parenthetical) (Details) - Stock Appreciation Rights (SARs) [Member] | 12 Months Ended
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Sep. 30, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Weighted-average remaining contractual life of outstanding SARs and stock options (in years) | 6 years 2 months 12 days
Weighted-average remaining contractual life of outstanding, exercisable SARs and stock options (in years) | 5 years 4 months 24 days
Exercise Price Range 1 [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Exercise price per share range, minimum (in usd per share) | $ 20.02
Exercise price per share range, maximum (in usd per share) | $ 29.5
Exercise price per share range, number of exercisable SARs and options | shares | 172,000
Exercise Price Range 2 [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Exercise price per share range, minimum (in usd per share) | $ 37.37
Exercise price per share range, maximum (in usd per share) | $ 47.63
Exercise price per share range, number of exercisable SARs and options | shares | 350,000
Exercise Price Range 3 [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Exercise price per share range, minimum (in usd per share) | $ 57.96
Exercise price per share range, maximum (in usd per share) | $ 59.95
Exercise price per share range, number of exercisable SARs and options | shares | 871,000
Exercise Price Range 4 [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Exercise price per share range, minimum (in usd per share) | $ 62.33
Exercise price per share range, maximum (in usd per share) | $ 82.34
Exercise price per share range, number of exercisable SARs and options | shares | 709,000

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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + 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)(iii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (e)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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