Comprehensive Income (Loss) - Reclassification adjustments out of accumulated other comprehensive loss (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Amortization of defined benefit pension items
Prior service cost	$ (16)
Actuarial losses	263
Total before tax	247
Tax benefit	(64)
Net of tax	$ 183	$ 138

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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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