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Stock-based Compensation Plans Schedule of Share-based Compensation, Option Disclosures by Ranges of Exercise Prices (Details)	12 Months Ended
	Sep. 30, 2015 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	3,992,666
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 6.54
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	4 years 2 months 1 day
Stock Options, Exercisable, Number | shares	3,799,877
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 6.43
Exercise Price Range 1 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Lower Range Limit	0.00
Stock Options, Exercise Price Range, Upper Range Limit	$ 4.99
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	1,395,711
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 3.34
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	5 years 5 months 2 days
Stock Options, Exercisable, Number | shares	1,395,711
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 3.34
Exercise Price Range 2 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Lower Range Limit	5.00
Stock Options, Exercise Price Range, Upper Range Limit	$ 9.99
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	1,799,892
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 6.07
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	4 years 3 months 2 days
Stock Options, Exercisable, Number | shares	1,607,103
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 5.74
Exercise Price Range 3 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Lower Range Limit	10.00
Stock Options, Exercise Price Range, Upper Range Limit	$ 14.99
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	515,846
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 11.30
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	2 years 7 days
Stock Options, Exercisable, Number | shares	515,846
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 11.30
Exercise Price Range 4 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Lower Range Limit	15.00
Stock Options, Exercise Price Range, Upper Range Limit	$ 20.99
Exercise Price Range 4 [Domain]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	281,217
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 16.76
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	10 months 2 days
Stock Options, Exercisable, Number | shares	281,217
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 16.76

X

- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ 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)(iii)



-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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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



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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=6415400&loc=d3e5070-113901

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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



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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

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-Publisher FASB



-Name Accounting Standards Codification



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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



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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



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