Defined Benefit Retirement Plan (Components of Net Periodic Pension Cost) (Details) - JVB Plan [Member] $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 125
Expected return on plan assets	(124)
Recognized net actuarial loss	28
Net periodic pension cost	29
Total recognized in other comprehensive income	(28)
Total recognized in net periodic pension benefit and other comprehensive income	$ 1

Amount recognized in net periodic benefit cost (credit) and other comprehensive (income) loss.

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Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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Amount of cost recognized for passage of time related to defined benefit plan.

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

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Amount of defined benefit plan cost (credit), classified as other.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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