Represents the percentage vested immediately when performance requirements have been earned.

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- Definition

Represents the market value of awards granted during the year.

+ References

No definition available.

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- Definition

Represents the percentage of amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement.

+ References

No definition available.

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- Definition

Represents maximum allowable payroll deductions for 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

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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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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

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

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ 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 (d)(2)

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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

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(2)

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Equity-based Incentive Plans (Details 4) (USD $)	12 Months Ended
Equity-based Incentive Plans (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Share-based Compensation Disclosures
Total expenses for the plan	$ 22,800,000	$ 15,200,000	$ 9,900,000
Employee Stock Option
Equity-Based Incentive Plans
Aggregate intrinsic value of options exercised (in dollars)	9,300,000	18,700,000	3,100,000
Aggregate intrinsic value of options that are currently outstanding and that are expected to be exercised (in dollars)	7,200,000
Unrecognized stock option compensation expense	0
Other Share-based Compensation Disclosures
Granted (in shares)	0	0	0
Executive Incentive Compensation Plan 2013
Equity-Based Incentive Plans
Original number of shares authorized for issuance	2,500,000
Remaining number of shares available for issuance	2,300,000
Executive Incentive Compensation Plan 2013 \| 2014 Award
Other Share-based Compensation Disclosures
Granted (in shares)	221,900
Market value of award	3,800,000
Executive Incentive Compensation Plan 2013 \| 2013 Award
Other Share-based Compensation Disclosures
Granted (in shares)	9,500
Market value of award	157,000
Executive Incentive Compensation Plan 2013 \| 2012 Award
Other Share-based Compensation Disclosures
Granted (in shares)	8,900
Market value of award	135,000
Executive Incentive Compensation Plan 2013 \| Vesting Based On Performance
Equity-Based Incentive Plans
Percentage Vested Immediately Based On Performance Earned	33.30%
Executive Incentive Compensation Plan 2013 \| Vesting Based On Service
Equity-Based Incentive Plans
Vesting period	2 years
Employee Stock Purchase Plan 2014
Other Share-based Compensation Disclosures
Maximum annual allowable payroll deduction per employee	10,400
Employer's matching contribution of employees' payroll deductions (as a percent)	10.00%
Total expenses for the plan	$ 376,000	$ 354,000	$ 354,000