Percentage of closing price at which employees can purchase common stock under the ESPP.

No definition available.

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- Definition

Share based compensation arrangements by Share-based payment award other than options grants in period weighted average exercise price.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Topic 718

-SubTopic 10

-Section S99

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: 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)

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

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- 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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- Definition

Percentage of vesting of share-based compensation awards.

+ 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

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

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Stock Based Compensation - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	2 Months Ended	9 Months Ended	12 Months Ended			1 Months Ended
	Apr. 30, 2014	Jan. 31, 2013	Oct. 31, 2012	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 30, 2012	Aug. 31, 2012	Jun. 30, 2013	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of award					10 years
Share based compensation granted under plan vest period					4 years
Weighted-average fair value per share of stock-based awards, granted to employees					$ 18.59	$ 22.86	$ 9.54
Stock-based compensation expense					$ 20,345,000	$ 11,127,000	$ 3,078,000
Proceeds from issuance of common stock	94,500,000	2,100,000	36,200,000	123,000,000			118,100,000
2013 Employee Stock Purchase Plan ("ESPP") [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock remain available for future grant					203,710
Number of shares approved under the plan										250,000
2014 Employment Commencement Incentive Plan (2014 Plan) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock remain available for future grant					640,000
Number of shares approved under the plan											640,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of common stock					85.00%
Common stock purchase					46,290
Proceeds from issuance of common stock					1,000,000
2002 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock remain available for future grant					0
2011 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock remain available for future grant					1,800,000
Number of shares approved under the plan					13,000,000
Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense					587,000	593,000	110,000
Granted shares							170,000	100,000	70,000
Exercise price of SARs								$ 23.85	$ 10.08
Stock Options with Service-and Performance-Based Conditions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation granted under plan vest period					4 years
Stock options granted to executives										400,000
Vested awards percentage					30.00%
Stock based compensation expense not yet recognized					9.1
Stock Options with Performance-based Conditions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense					1,200,000
Service-Vesting Conditions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense not yet recognized					$ 40.9