Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Percentage of vesting of share-based compensation awards.

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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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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Share Based Compensation Share Based Compensation (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	1,846		2,892
Number of LTIP shares authorized	20,000,000		20,000,000
Allocated Share-based Compensation Expense	$ 162,000	$ 132,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 39,000	$ 32,000
5 Year Vesting Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted		109,819
Vesting period		5 years
Percentage vested per year		20.00%
Expiration period		10 years
7 Year Vesting Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards granted		28,306
Vesting period		7 years
Percentage vested per year		14.29%
Expiration period		10 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years		3 years
Minimum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Maximum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years