Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Estimated Forfeiture Rate

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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

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-Publisher FASB
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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ 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

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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 estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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 shares authorized for issuance under share-based payment arrangement.

+ 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.

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- Definition

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

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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Stock Options And Employee Stock Purchase Plan (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Number of options outstanding	551,739		551,739		707,777
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Estimated Forfeiture Rate			13.21%	11.71%
Cash received upon the issuance of common stock			$ 1,995	$ 135
Share-based Payment Arrangement, Expense	$ 6,446	$ 7,906	18,394	21,393
Share-based Payment Arrangement, Option [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	7,100		$ 7,100		$ 6,900
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			6 years 2 months 12 days
Share-based Payment Arrangement, Expense	$ 200	200	$ 700	$ 700
Restricted (Performance) Stock [Member]
Shares, Granted			74,051	473,501
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			2.53%	2.89%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			28.30%	28.40%
Restricted Stock [Member]
Number of stocks outstanding	1,130,260		1,130,260		1,207,011
Shares, Granted			171,617
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			5 years 2 months 12 days
Restricted Stock Units (RSUs) [Member]
Number of stocks outstanding	24,629		24,629		41,231
Shares, Granted			3,844
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			3 years 3 months 18 days
2007 Stock Plan [Member]
Maximum issuance of common stock	4,500,000		4,500,000
Number of options outstanding	128,739		128,739
Number of stocks outstanding	1,940		1,940
2015 Stock Option Plan [Member]
Maximum issuance of common stock	4,200,000		4,200,000
Number of options outstanding	423,000		423,000
Number of stocks outstanding	22,689		22,689
2001 Employee Stock Purchase Plan [Member] \| Common Stock [Member]
Market value of common stock on the date of grant for incentive stock options			85.00%
Maximum earnings withheld by the employees	15.00%		15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Estimated Forfeiture Rate			0.78%	0.10%
Number of shares purchased under the plan			32,154	1,781
Cash received upon the issuance of common stock			$ 2,000	$ 100
Number of shares available for issuance	1,557,827		1,557,827
Share-based Payment Arrangement, Expense	$ 300	$ 300	$ 1,000	$ 400
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			2.43%	2.02%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			15 days	15 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			1.05%	1.03%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			26.80%	22.21%
Minimum [Member]
Market value of common stock on the date of grant for incentive stock options			85.00%