Unvested shares to be recognized.

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Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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No definition available.

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

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

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Number of shares issued under share-based payment arrangement.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Shareholders' Equity - 2012 Long-Term Incentive Plan (Details) - USD ($)				12 Months Ended
	Apr. 26, 2019	Jan. 01, 2019	May 25, 2018	Dec. 31, 2019	Dec. 31, 2018
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Compensation expense not yet recognized				$ 0
Expense recognized for issuance of restricted shares				$ 316,000	$ 276,000
Unvested Shares Recognized				286,000
Non-employee directors
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of restricted stock issued	7,836		4,288
Compensation expense not yet recognized	$ 100,000		$ 40,000
2012 Long Term Incentive Plan
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of restricted stock shares vested		26,250
Number of shares withheld and repurchased		9,729
Value of shares withheld and repurchased		$ 99,000
2012 Long Term Incentive Plan \| Executive Officer
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of restricted stock issued			78,750
Compensation expense not yet recognized			$ 735,000
2012 Long Term Incentive Plan \| Non-employee directors
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period of restricted share awards			12 months