Deferred compensation arrangement, shares credited to directors accounts.

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- Definition

Employee stock purchase threshold as a percentage of the combined voting power of the Company

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- Definition

Share-Based compensation award by Share-based payment award, purchase price as percent of fair value

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- Definition

Weighted average stock price of shares credited under Director Deferred Compensation Plan

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- Definition

Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification
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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.

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- Definition

Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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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

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

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

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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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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

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- Definition

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

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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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- Definition

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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- Definition

Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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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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Share-Based Compensation Plans (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 19, 2019	Jun. 10, 2009
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Weighted average grant-date fair value of options granted	$ 1.77	$ 1.23	$ 1.97
Total intrinsic value of options exercised	$ 385,000	$ 399,000	$ 132,000
Intrinsic value of shares vested	$ 357,000	$ 242,000	$ 3,800,000
Vesting of nonvested shares, shares	129,675	53,050	1,100,000
Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized share-based compensation expense, weighted average period	2 years 3 months 18 days
Restricted Stock [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized compensation cost		$ 3,900,000
Performance Based Award [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized share-based compensation expense, weighted average period	1 year 8 months 12 days
Employees and directors [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized share-based compensation expense, options	$ 20,300,000
1999 EIP [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	2,000,000
2009 EIP [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	0					29,200,000
Deferred Compensation Arrangement with Individual, Maximum Contractual Term	10 years
2009 EIP [Member] \| Minimum [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period, minimum	3 years
2009 EIP [Member] \| Maximum [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period, minimum	4 years
2019 EIP [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized					40,200,000
2009 ESPP [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	166,666
Share-Based compensation award by Share-based payment award, purchase price as percent of fair value	85.00%
Employee stock purchase threshold as a percentage of the total combined voting power of the Company	5.00%
Share-based compensation awards expiration date	Jun. 10, 2019
Proceeds from Stock Plans	$ 1,600,000	$ 1,200,000	$ 1,000,000
Shares issued under ESPP	84,703	140,313	121,183
2009 ESPP [Member] \| Employees and directors [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Maximum number of shares allowed to be purchased by employees	3,333
2019 ESPP [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	425,000			500,000
Shares issued under Director Deferred Compensation Plan	72,081
Shares credited under Director Deferred Compensation Plan	412,435
Weighted average stock price of shares credited under Director Deferred Compensation Plan	$ 4.52
2015 IEP [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,500,000