Defined Benefit Pension Plans Amounts reported in the consolidated balance sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Defined benefit plan disclosure [Line Items]
Current liability	$ (187)	$ (175)
Noncurrent liability	(3,119)	(12,123)
Funded status of the plans	$ (3,306)	$ (12,298)