Options may be granted to purchase specified number of common shares under stock option plan, maximum term.

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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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.

+ References

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- Definition

Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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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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-Publisher FASB
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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 number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock Option And Stock Award Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	1,628,903	890,116	608,520	500,919
Options may be granted to purchase specified number of common shares under stock option plan, maximum term	10 years
The total intrinsic value of stock options exercised	$ 0.1	$ 0.4	$ 0.2
The grant-date fair value of stock option-based awards vested	0.5	$ 0.1	$ 0.4
Restricted Stock or Unit Expense	$ 1.3
Stock options exercisable	360,218	275,392
Total stock options available for grant	954,454
Restricted Stock [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Option vesting period	3 years
Stock Option Based Awards [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost	$ 1.9
Weighted average period for the cost expected to be recognized	397 days
Non-Vested Restricted Stock And Other Stock-Based Awards
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost	$ 2.5
Weighted average period for the cost expected to be recognized	525 days
Share-based Payment Arrangement, Tranche Two [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	5 years
Share-based Payment Arrangement, Tranche One [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	7 years
Share-based Payment Arrangement, Tranche Two [Member] \| Stock Option Based Awards [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Option vesting period	2 years
Share-based Payment Arrangement, Tranche One [Member] \| Stock Option Based Awards [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Option vesting period	3 years