Retirement Plans (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
401(k) plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Minimum service period	0 years
Minimum age restriction for participation	21 years
Maximum voluntary percentage contributions of salary (as a percent)	86.00%
Contribution percentage, company match as percent of employee contribution	3.00%
Contribution percentage, percent of company match after initial threshold	50.00%
Contribution percentage, initial threshold for change in company matching contribution	3.00%
Matching contributions by employer	$ 66,000	$ 76,000
401(k) plan [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution percentage, company match as percent of employee contribution	5.00%
Profit Sharing [Member]
Defined Benefit Plan Disclosure [Line Items]
Minimum age restriction for participation	21 years
Matching contributions by employer	$ 0
Minimum number of service hours required in plan year to be eligible under plan	900 hours

Defined Contribution Plan, Employer Matching Contribution After Initial Threshold, Percent

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- Definition

Defined Contribution Plan, Initial Threshold For Change In Company Matching Contribution

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- Definition

The minimum age of employees eligible to participate in the 401(k) retirement plan on hire date.

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- Definition

Minimum Number Of Service Hours Required To Be Eligible For Plan

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- Definition

Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

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

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

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

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No definition available.

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