Percentage Of Stock Options Vested

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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

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

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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- Definition

The cash inflow associated with the amount received from the stock plan during the period.

+ References

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-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph a

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-Glossary Financing Activities

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- Definition

The discount rate from market value on offering date that participants pay for shares.

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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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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- 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

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

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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

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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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph b(1)(b)

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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-Name Accounting Standards Codification

-Topic 505

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-Section S99

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Stock Options And Employee Stock Purchase Plan (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Y	Sep. 30, 2011	Dec. 31, 2011
Allocated Share-based Compensation Expense	$ 2,403,000	$ 2,248,000	$ 6,851,000	$ 6,684,000
Weighted-average grant date fair value of options granted			$ 7.92	$ 13.12
Number of options outstanding	1,803,634		1,803,634		2,087,695
Number of options granted			67,000
Cash received upon the issuance of common stock			109,000	110,000
Percentage of stock options vested			20.00%
Expiration period of options granted (in years)			10
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value			4,000,000	38,900,000
Stock Options [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	5,800,000		5,800,000		9,000,000
Restricted Stock And Restricted Stock Unit (RSU) [Member]
Allocated Share-based Compensation Expense	1,600,000		3,700,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	16,600,000		16,600,000		11,300,000
Employee Stock Purchase Plan [Member]
Market value of common stock on the date of grant for incentive stock options			95.00%
Maximum earnings withheld by the employees	15.00%		15.00%
Number of shares purchased under the plan			4,115	4,127
Cash received upon the issuance of common stock			$ 109,000	$ 110,000
Number of shares available for issuance	1,647,283		1,647,283
Restricted Stock [Member]
Number of stocks outstanding	811,350		811,350		742,683
Restricted Stock Units (RSUs) [Member]
Number of stocks outstanding	95,466		95,466		32,750
1997 Stock Option Plan [Member]
Additional shares authorized for issuance			840,000
Maximum issuance of common stock	12,000,000		12,000,000
1997 Stock Option Plan [Member] \| Stock Options [Member]
Number of options outstanding	803,761		803,761
1997 Stock Option Plan [Member] \| Restricted Stock [Member]
Number of stocks outstanding	0		0
2007 Stock Plan [Member]
Number of options outstanding	999,873		999,873
Number of stocks outstanding	95,466		95,466
Maximum issuance of common stock	4,500,000		4,500,000
Minimum [Member]
Market value of common stock on the date of grant for incentive stock options			85.00%