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		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Number of options outstanding	476,811		476,811		518,341
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Estimated Forfeiture Rate			11.52%	12.98%
Cash received upon the issuance of common stock			$ 3,303	$ 1,995
Share-based Payment Arrangement, Expense	$ 6,530	$ 6,862	12,843	11,948
Share-based Payment Arrangement, Option [Member]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	6,300		$ 6,300		$ 6,800
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			5 years 6 months
Share-based Payment Arrangement, Expense	$ 200	200	$ 400	$ 500
Restricted (Performance) Stock [Member]
Shares, Granted			82,112	74,051
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			0.70%	2.50%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			27.00%	28.30%
Restricted Stock [Member]
Number of stocks outstanding	858,863		858,863		1,105,059
Shares, Granted			1,268
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			4 years 7 months 6 days
Restricted Stock Units (RSUs) [Member]
Number of stocks outstanding	210,814		210,814		20,874
Shares, Granted			197,078
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			5 years
2007 Stock Plan [Member]
Maximum issuance of common stock	4,500,000		4,500,000
Number of options outstanding	53,811		53,811
Number of stocks outstanding	0		0
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	210,814		210,814
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			16.50%	0.78%
Number of shares purchased under the plan			53,694	32,154
Cash received upon the issuance of common stock			$ 3,300	$ 2,000
Number of shares available for issuance	1,469,874		1,469,874
Share-based Payment Arrangement, Expense	$ 600	$ 300	$ 1,100	$ 600
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			0.10%	2.40%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			6 months	6 months
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			0.00%	1.10%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			24.00%	26.80%
Minimum [Member]
Market value of common stock on the date of grant for incentive stock options			85.00%