Normal Retirement Age

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- Definition

Retirement benefit as percentage of compensation.

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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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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

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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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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

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

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

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Percentage of vesting of award under share-based payment arrangement.

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Number of non-vested options outstanding.

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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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Pension and Equity Incentive Plans (Narrative) (Details) - USD ($)			3 Months Ended
	Jun. 14, 2019	Dec. 14, 2018	Mar. 31, 2020	Mar. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Options granted
Shares underlying unexercised options			684,675
Expected future expenses relating to non-vested restricted shares			$ 604,000	$ 624,000
Expected future compensation expense, unexercised options			$ 1,300,000
Expected future compensation expense, weighted average period for recognition			4 years 8 months 5 days
Exercisable - Number of Options			515,800	268,633
Restricted Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected future compensation expense, weighted average period for recognition			1 year 18 days	1 year 8 months 16 days
2018 Equity Incentive Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares authorized for issuance			1,000,000
2011 Stock Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares authorized for issuance			900,000
Supplemental Executive Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic pension cost			$ 1,800	$ 3,000
Normal retirement age			65 years
Retirement benefit as percentage of compensation			75.00%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic pension cost			$ 45,000	$ 40,000
Directors [Member] \| 2018 Equity Incentive Plan [Member] \| Options [Member]
Defined Benefit Plan Disclosure [Line Items]
Options granted	68,750	300,000
Vesting period	2 years	2 years
Directors [Member] \| 2018 Equity Incentive Plan [Member] \| Restricted Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Restricted stock issued	33,110	54,000
Vesting period	2 years	2 years
Directors [Member] \| Tranche 1 And 2 [Member] \| 2018 Equity Incentive Plan [Member] \| Options [Member]
Defined Benefit Plan Disclosure [Line Items]
Vesting percentage	50.00%	50.00%
Executive Officers [Member] \| 2018 Equity Incentive Plan [Member] \| Options [Member]
Defined Benefit Plan Disclosure [Line Items]
Options granted	30,125
Vesting period	2 years
Executive Officers [Member] \| 2018 Equity Incentive Plan [Member] \| Restricted Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Restricted stock issued	14,508	13,321
Vesting period	2 years	2 years