Aggregate Limit Of Shares Issuable To Incentive Stock Option Awards

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Annual Increase In Number Of Shares Of Common Stock

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Increase Decrease In Share Based Compensation

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Number Of Share Based Equity Incentive Plan

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- Definition

Restricted Stock Unit Conversion Into Shares Period

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage Monthly

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Percentage Yearly

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- Definition

Share Based Compensation Share Based Awards Employee Termination Unvested Awards Forfeiture Period Maximum

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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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

Unrecognized cost of unvested options awarded to employees as compensation.

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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.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Subparagraph (f)(2)(i)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

Number of non-option equity instruments exercised by participants.

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- Definition

Number of shares under non-option equity instrument agreements that were either cancelled or expired.

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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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)

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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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended	0 Months Ended	3 Months Ended
	Mar. 31, 2015 Incentive_Plan	Dec. 20, 2013	Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity incentive plans	2
Shares authorized	225,000,000us-gaap_CommonStockSharesAuthorized			225,000,000us-gaap_CommonStockSharesAuthorized
Total unrecognized compensation expense	$ 9,884,000
Vesting period	2 years 4 months 24 days
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	7,856,374
Annual increase in number of shares of common stock	4.00%
Aggregate limit of shares issuable to incentive stock option awards	3,000,000
Initial grant of stock-based compensation in shares		6,000,000
Increase in percentage of outstanding number of shares of common stock		4.00%
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested grant yearly	25.00%
Percentage of vested grant monthly	75.00%
Term of years	10 years
Vesting period of grant date	3 years
Exercise price	$ 20.00
Number of SARs, outstanding	110,593		110,593
Number of SARs, Granted	0
Number of SARs, Exercised	0
Number of SARs, Forfeited	0
Reduced compensation expense	$ 0		$ 0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units vest and convert into shares of our common stock	1 year
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of years	10 years
Vesting period of grant date	3 years
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of grant date	1 year
Restricted Stock Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units vest and convert into shares of our common stock	4 years
Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested grant yearly	25.00%
Percentage of vested grant monthly	75.00%
Term of years	4 years
Unexercised vested option forfeiture	3 months
Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of years	10 years
Vesting period of grant date	3 years