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Share-Based Compensation - Options by Exercise Price (Details) | 12 Months Ended
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Sep. 30, 2020 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of outstanding options (in share) | shares | 1,408,036
Weighted average exercise price (in dollars per share) | $ 38.79
Weighted average remaining term (in years) | 4 years 1 month 28 days
$0 - $5,00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 0
Exercise price range, upper range limit | $ 5.00
Number of outstanding options (in share) | shares | 0
$5.00 - $10.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 5.00
Exercise price range, upper range limit | $ 10.00
Number of outstanding options (in share) | shares | 0
$10.00 - $15.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 10.00
Exercise price range, upper range limit | $ 15.00
Number of outstanding options (in share) | shares | 0
$15.00 - $20.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 15.00
Exercise price range, upper range limit | $ 20.00
Number of outstanding options (in share) | shares | 0
$20.00 - $25.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 20.00
Exercise price range, upper range limit | $ 25.00
Number of outstanding options (in share) | shares | 0
$25.00 - $30.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 25.00
Exercise price range, upper range limit | $ 30.00
Number of outstanding options (in share) | shares | 420,000
Weighted average exercise price (in dollars per share) | $ 25.91
Weighted average remaining term (in years) | 1 year 4 months 9 days
$30.00 - $35.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 30.00
Exercise price range, upper range limit | $ 35.00
Number of outstanding options (in share) | shares | 0
$35.00 - $40.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 35.00
Exercise price range, upper range limit | $ 40.00
Number of outstanding options (in share) | shares | 126,161
Weighted average exercise price (in dollars per share) | $ 39.65
Weighted average remaining term (in years) | 2 years 7 days
$40.00 - $45.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 40.00
Exercise price range, upper range limit | $ 45.00
Number of outstanding options (in share) | shares | 859,875
Weighted average exercise price (in dollars per share) | $ 44.92
Weighted average remaining term (in years) | 5 years 10 months 2 days
$45.00 - $50.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 45.00
Exercise price range, upper range limit | $ 50.00
Number of outstanding options (in share) | shares | 0
$50.00 - $55.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 50.00
Exercise price range, upper range limit | $ 55.00
Number of outstanding options (in share) | shares | 0
$55.00 - $60.00 [Member] |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Exercise price range, lower range limit | $ 55.00
Exercise price range, upper range limit | $ 60.00
Number of outstanding options (in share) | shares | 2,000
Weighted average exercise price (in dollars per share) | $ 55.28
Weighted average remaining term (in years) | 1 year 10 months 20 days

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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=120381028&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + 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)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&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=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices. + 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)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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