Pension (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Pension [Abstract]
Expected pension expense	$ 500			$ 500
Pension Contributions		$ 1,000		1,000
Pension expense	$ 125		$ 116	$ 375	$ 344	$ 459

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- Definition

Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

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- Definition

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

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- Definition

Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

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