Effective date of employment agreement.

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Performance-based awards, awards granted, grant date market price.

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- Definition

Share based compensation arrangement by share based payment award, equity instruments other than options, dividend equivalents number.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options maximum shares to be earned.

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- Definition

Share based compensation average annual stock holders return percentage description.

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- Definition

Share based compensation equity award for full performance period other than options for grant price per share.

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No definition available.

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- Definition

Share based compensation equity award for interim period other than options for grant price per share.

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No definition available.

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- Definition

Shareholder return average annual return threshold net.

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Shares granted to key employee.

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- Definition

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

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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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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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- Definition

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

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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).

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- Definition

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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- Definition

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

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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No definition available.

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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 fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Number of shares issued under share-based payment arrangement.

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Share-Based Compensation (Narrative) (Details) - USD ($)			12 Months Ended
	Jun. 15, 2018	Jun. 15, 2011	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value per share			$ 17.48
Fair value of vested shares			$ 938,000	$ 485,000	$ 7,556,000
Shares vested			59,000
Shares forfeited			7,000
Grant date market price	$ 28.91
Shares granted under Stock incentive plan			63,000
Effective date of the employment agreement	Jun. 15, 2023
Maximum shares to be earned			114,000
Share based compensation average annual total stock holders return, description			The percentage of the market performance-based equity award to be earned will be determined based on the Company’s average annual TSR over the Interim Performance Period and/or over the Full Performance Period as follows: if average annual TSR (1) is below 4%, the percentage of grant earned would be 0%, (2) equals 4%, the percentage of grant earned would be 33.3%, (3) equals 6.5%, the percentage of grant earned would be 66.7%, and (4) equals 10% or above, the percentage of grant earned would be 100%.
Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to Company's President		378,800
Average annual TSR threshold		6.50%
Vesting period		7 years
Time-Based Awards [Member] \| Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested	189,400
Performance-Based Shares [Member] \| Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares forfeited	189,400
Time-Based Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares will vest upon the fifth anniversary	152,000
Market Performance-Based Equity Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, interim period other than option grant, price per share	$ 21.78
Share based compensation, full performance period other than option grant, price per share	$ 19.60
Market Performance-Based Equity Award [Member] \| Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted under Stock incentive plan	227,000
Dividend equivalent rights	227,000
2017 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under Stock Incentive Plan	38,000		300,000
Aggregate cost of awards not yet recognized			$ 5,800,000
Unrecognized cost recognition period			2 years 1 month 6 days
Shares granted under Stock incentive plan	114,000
2017 Plan [Member] \| Time-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued			63,000	79,000	92,000
Weighted-average grant date fair value per share			$ 17.48	$ 21.25	$ 32.54
New Amended and Restated Employment Agreement [Member] \| Time-Based Restricted Shares [Member] \| Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to Company's President	152,000
Grant date market price	$ 28.91