Business Segments (Reconciliation of Operating Profit (Loss) from Segments to Consolidated) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting [Abstract]
Profit for reportable segments	$ 16,351	$ 12,710	$ 25,352	$ 16,661
Interest expense - net	1,597	1,630	2,952	3,517
Other income (expense)	252	(128)	402	477
Unallocated corporate expenses and other unallocated charges	(3,757)	(4,790)	(7,225)	(8,792)
Income before income taxes	$ 11,249	$ 6,162	$ 15,577	$ 4,829

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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- Definition

The net amount of operating interest income (expense).

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Amount of income (expense) related to nonoperating activities, classified as other.

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