Represents the number of different vesting criteria of RSU's issued by the entity.

No definition available.

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- Definition

Represents the number of shares included in the authorized shares which was previously reserved for issuance under the plan.

+ 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

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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.

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- Definition

Percentage of vesting of share-based compensation awards.

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-Publisher FASB

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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.

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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).

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB

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- Definition

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.

+ References

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

+ References

No definition available.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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-Publisher FASB

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-based Compensation (Details) (USD $)	3 Months Ended		0 Months Ended	12 Months Ended
Stock-based Compensation (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	May 07, 2014	Dec. 31, 2014
Stock-based Compensation
Stock-based compensation expense	$ 3,100,000	$ 3,400,000
Equity Incentive Plan 2010
Stock-based Compensation
Shares included in the authorized shares which was previously reserved for issuance	1,648,524
Shares
Granted (in shares)			0
Equity Incentive Plan 2014
Stock-based Compensation
Number of shares authorized	6,648,524
Employee and Directors Stock Options
Stock-based Compensation
Term of award	10 years
Vesting period	3 years
Unrecognized compensation cost	0
Stock-based compensation expense	0	0
Shares
Balance at the beginning of the period (in shares)	3,312,158
Balance at the end of the period (in shares)	3,312,158			3,312,158
Vested and exercisable at the end of the period (in shares)	3,312,158
Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 20.40
Balance at the end of the period (in dollars per share)	$ 20.40			$ 20.40
Vested and exercisable at the end of the period (in dollars per share)	$ 20.40
Remaining Contractual Term
Beginning of the period	5 years 2 months 27 days			5 years 5 months 27 days
End of the period	5 years 2 months 27 days			5 years 5 months 27 days
Vested and exercisable at the end of the period	5 years 2 months 27 days
Aggregate Intrinsic Value
Balance at the beginning of the period	46,077,000
Balance at the end of the period	57,438,000			46,077,000
Vested and exercisable at the end of the period	57,438,000
Restricted Stock Units
Stock-based Compensation
Number of different vesting criteria	3
Vesting period	3 years
Unrecognized compensation cost	26,900,000
Stock-based compensation expense	$ 3,100,000	$ 3,400,000
Restricted Stock With Book Value Conditions
Stock-based Compensation
Vesting period	3 years
Restricted Stock With Total Shareholder Return Conditions
Stock-based Compensation
Vesting period	3 years
Restricted Stock With Total Shareholder Return Conditions \| Minimum
Stock-based Compensation
Percentage of shares vested	0.00%
Restricted Stock With Total Shareholder Return Conditions \| Maximum
Stock-based Compensation
Percentage of shares vested	200.00%