Stock-based Compensation (Additional Information) (Details) (USD $)	9 Months Ended
Dec. 31, 2012
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, granted	734,500
Stock Options [Member] \| Equity Incentive Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, vesting period	3 years
Options, expiration term	7 years
Options, weighted-average estimated fair value of options granted	5.38
Time Vested Restricted Stock Units [Member] \| Equity Incentive Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, granted	93,900
Restricted stock units, vesting term	3 years
Restricted stock units, weighted average grant date fair value	10.86
Performance Based RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, granted	92,820
Restricted stock units, vesting term	3 years
Restricted stock units, forfeited	6,300
Restricted stock units, weighted average grant date fair value	10.86

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vesting Term

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Estimated Weighted Average Fair Value Per Share

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Number Of Installments For Vesting Period

+ References

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Expiration Term

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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- Definition

The number of grants made 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

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ 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)(i)-(ii)

-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 b(2)(b)

-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)(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.

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- Definition

Net number of share options (or share units) granted during the period.

+ References

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