Business Segments - Reconciliation of Operating Profit (Loss) from Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting [Abstract]
Profit for reportable segments	$ 3,217	$ 16,351
Interest expense - net	(1,090)	(1,597)	$ (1,907)	$ (2,952)
Other income - net	(3,339)	252	(4,085)	402
Income (loss) before income taxes	$ 1,616	$ 11,249	$ (1,078)	$ 15,577