Employee Stock Purchase Plan, Number Of Shares Available for Issuance

No definition available.

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- Definition

Maximum percentage of market-performance based restricted stock units during vesting period.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Shares Remaining Available For Issuance

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-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 h

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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Stock-based Compensation - Additional Information (Details) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended			3 Months Ended
	May 31, 2011 Incentive Plan 2005	May 19, 2011 Incentive Plan 2005	Mar. 31, 2013 Amended And Restated 2005 Stock Incentive Plan	Mar. 31, 2013 Employee Stock Purchase Plan 2010	Mar. 31, 2013 Restricted Stock Units (RSUs)	Mar. 31, 2013 Market Performance Based Restricted Stock Units	Mar. 31, 2013 Market Performance Based Restricted Stock Units Minimum	Mar. 31, 2013 Market Performance Based Restricted Stock Units Maximum	Mar. 31, 2013 Stock Options	Mar. 31, 2013 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approved increase in shares	3,000,000
Shares reserved for issuance		16,283,379	5,000,000
Total unamortized compensation cost					$ 44.2	$ 8.8			$ 3.9	$ 3.4
Weighted average period of total unamortized cost (in years)					3 years	2 years			1 year 3 months 18 days	1 year
Vesting period of granted market-performance based restricted stock units							2 years	3 years
Percentage of market-performance based restricted stock units eligible to vest over the vesting period								150.00%
Maximum number of shares available				2,400,000
Number of shares remaining				1,738,963