The exercise price of each option on the fair value of the entity stock on the date of grant.

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The option price as percentage of fair value for grant of stock options on the date of grant.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The shareholding percentage for grant of stock options on the date of grant.

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Amount of noncash expense for 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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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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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may 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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. 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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Number of shares issued under share-based payment arrangement.

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Description of terms of award under share-based payment arrangement.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Benefit Plans, Stock Based Compensation Plans - Equity Awards (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	May 31, 2019
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Stock based compensation expense	$ 5	$ 173	$ 150
Stock Options [Member]
Summary of Changes in Stock Option Awards [Roll Forward]
Beginning balance (in shares)	554,641
New options awarded (in shares)	0
Expired options (in shares)	(5,750)
Options forfeited (in shares)	0
Exercised options (in shares)	(29,800)	(177,000)	(784,000)
Ending balance (in shares)	519,091	554,641
Stock Option Awards, Exercisable [Roll Forward]
Ending balance (in shares)	486,791
Weighted Average Exercise Price [Roll Forward]
Beginning balance (in dollars per share)	$ 6.65
New options awarded (in dollars per share)	0
Expired options (in dollars per share)	0
Options forfeited (in dollars per share)	0
Exercised options (in dollars per share)	6.21
Ending balance (in dollars per share)	$ 6.67	$ 6.65
Additional Disclosures [Abstract]
Weighted average remaining contractual life, options outstanding	4 years 6 months
Exercisable options, weighted average exercise price (in dollars per share)	$ 6.69
Weighted average remaining contractual life, exercisable outstanding	4 years 6 months
Intrinsic value of outstanding stock options	$ 1,020
Intrinsic value of vested stock options	952
Restricted Common Shares [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Stock based compensation expense	$ 5	$ 173	$ 150
2010 Directors Stock Option Plan [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Shares available for grant (in shares)				2,000,000
2010 Directors Stock Option Plan [Member] \| Stock Options [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Options maximum term	10 years
Options maximum term	5 years
2019 Equity Incentive Plan [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Shares available for grant (in shares)	1,700,000			2,000,000
Exercise price as percentage of fair value	100.00%
Shareholding percentage for grant of stock options	10.00%
Option price as percentage of fair value	110.00%