Employee Benefit Plans - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	96,000	203,000	47,100
Defined contribution plan, maximum annual contributions per employee, percent	80.00%
Employer, contribution	$ 648	$ 601	$ 492
Deferred fees	379	297	149
Interest paid on deferred fees	107	67	44
Deferred compensation arrangement with individual, distributions paid	$ 14	$ 14	$ 8
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation arrangement, option to elect to defer fees and bonuses, percentage	100.00%
Executive Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation arrangement, option to elect to defer fees and bonuses, percentage	100.00%
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Award expiration period	10 years
Options granted (in shares)	96,000	203,000	47,100
Compensation cost not yet recognized	$ 1,100
Compensation cost not yet recognized, weighted average period	2 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Granted (in shares)	46,050	47,550	38,400
Compensation cost not yet recognized	$ 1,600
Compensation cost not yet recognized, weighted average period	2 years 8 months 12 days
Other Postretirement Benefits Plan \| Executive Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage	100.00%
Accrued employee benefits	$ 115	$ 88	$ 90
Life settlement contracts, fair value	250
Life settlement contracts, expense	$ 5	$ 18	$ 5
2019 Equity Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	500,000
Number of shares available for grant (in shares)	443,100
2019 Equity Compensation Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	41,000
Granted (in shares)	15,900

Deferred fees

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Interest paid on deferred fees

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Share Based Compensation Arrangement By ShareBased Payment Award Award Expiration Period

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Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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Commitment made to pay deferred cash remuneration expressed as a percentage of the individual's base salary.

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Amount of distribution made to individual in accordance with deferred compensation arrangement.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method.

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Period expense related to postemployment benefits.

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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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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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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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Gross 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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