Comprehensive Income (Loss) - Reclassification adjustments out of accumulated other comprehensive loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Amortization of defined benefit pension items
Prior service cost	$ (63)	$ (63)
Actuarial losses	689	697
Total before tax	626	634
Tax benefit	(163)	(165)
Net of tax	$ 463	$ 469

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

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