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Share-Based Compensation - Options by Exercise Price (Details) | 12 Months Ended
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Sep. 30, 2018 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] |
Number of Outstanding Options | shares | 835,454
Weighted Average Exercise Price | $ 29.27
Weighted Average Remaining Term (in years) | 3 years 4 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 | $ 0.00
Exercise Price Range, Upper Range Limit | $ 5.00
Number of Outstanding Options | 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 | 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 | 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 | 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 | shares | 28,668
Weighted Average Exercise Price | $ 20.54
Weighted Average Remaining Term (in years) | 3 months 7 days
$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 | shares | 580,000
Weighted Average Exercise Price | $ 25.91
Weighted Average Remaining Term (in years) | 3 years 4 months 13 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 | shares | 49,656
Weighted Average Exercise Price | $ 31.37
Weighted Average Remaining Term (in years) | 1 year 3 months 11 days
$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 | shares | 100,330
Weighted Average Exercise Price | $ 38.77
Weighted Average Remaining Term (in years) | 2 years 3 months 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 | shares | 74,800
$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 | 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 | shares | 2,000

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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. + Details
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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=96867065&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://www.xbrl.org/2003/role/presentationRef -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=96867065&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=96867065&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://www.xbrl.org/2003/role/presentationRef -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=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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