Share-based Compensation Arrangement by Share-based Payment Award, Offering Period

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Cliff Vesting Period

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Vesting Period

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Value Purchased By Award

+ References

No definition available.

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- Definition

Share Based Compensation Arrangements By Share Based Payment Award Option Expiration Period

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No definition available.

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- Definition

Share Based Compensation Arrangements By Share Based Payment Award Restricted Stock Units Vesting Period

+ References

No definition available.

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The discount rate from market value on purchase date that participants pay for shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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)(2)(iii)(1)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64, 65

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Stock Based Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant under the 2007 Plan (shares)	2,309,000		2,309,000
Option vesting period (years)			4 years
Percentage discount from fair market value for shares purchased under the Employee Stock Purchase Plan			85.00%
Offering period (years)	6 months
Shares available for future issuance under the Employee Stock Purchase Plan (shares)	713,000		713,000
Prior to October 1 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option expiration period (years)			10 years
After October 1 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option expiration period (years)			7 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option Cliff vesting period			6 months
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option Cliff vesting period			1 year
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of grants			$ 9.14	$ 9.36
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU vesting period (years)			2 years
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU vesting period (years)			4 years
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized stock-based compensation expense	$ 12.3		$ 12.3
Nonvested awards, total compensation cost not yet recognized, period for recognition (years)			2 years 9 months 15 days
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized stock-based compensation expense	0.2		0.2
Nonvested awards, total compensation cost not yet recognized, period for recognition (years)			4 months
Weighted-average fair value of grants	$ 2.30	$ 2.98	$ 2.30	$ 2.98
Shares purchased under the ESPP			105,000	97,000
Amount purchased under the ESPP			$ 0.8	$ 0.7