Share-Based Compensation Arrangement by Share-based Payment Award, Forfeiture Rate

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Cashless Method

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- Definition

Share Based Compensation Arrangement By ShareBased Payment Award Maximum Value Eligible To Purchase During Period

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Shares Issued, Underwriting Discount, Per Share

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Shares Repurchased

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Window Period

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

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

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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

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of shares authorized for issuance under share-based payment arrangement.

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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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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.

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- Definition

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of shares purchased for issuance under share-based payment arrangement.

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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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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Common Stock And Stock Options (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
	Aug. 20, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares of common stock for which awards can be granted		183
Number of Shares, Awards granted		79	98	303
Maximum amount of common stock participants may elect to purchase		$ 100
Window period		20 days
Shares repurchased under management purchase program		0	0	0
Weighted average remaining contractual life of options exercisable, years		4 years 6 months 11 days	4 years 9 months 22 days
Total intrinsic value of options exercised		$ 1,627	$ 25,724	$ 631
Weighted average fair value of options granted				$ 4.20
Forfeiture rate		0.00%
Stock option expense		$ 1,886	$ 1,395	$ 844
Stock options exercised using cashless method		11	38
Unrecognized compensation costs related to non-vested awards		$ 1,957
Unrecognized compensation costs related to non-vested awards, recognition period		1 year 9 months 26 days
Issuance of common stock	$ 88,967		$ 88,967
Issuance of common stock, shares	1,725
Price per share	$ 55.00
Underwriting discount, per share	$ 3.30
Shares repurchased	500
2015 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares of common stock for which awards can be granted		500
Number of Shares, Awards granted		0	0	0
2006 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares of common stock for which awards can be granted		369
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares approved under purchase plan		300
Shares purchased for award		9	7	11
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Awards granted			0	303
Stock Options [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		10 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Awards granted		79	98
Vesting period		3 years
Weighted average fair value of units granted		$ 23.83	$ 20.61