Information on Business Segments (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) Segment	Jun. 30, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment			2
Net sales	$ 371,669	$ 375,315	$ 748,360	$ 741,975
Operating profit	56,957	63,879	107,607	120,512
Interest expense	5,399	4,133	10,512	8,025
Other expense (income), net	1,712	947	3,519	2,710
Income before income taxes	49,846	58,799	93,576	109,777
Aerospace [Member]
Segment Reporting Information [Line Items]
Net sales	138,265	125,739	272,454	246,437
Net sales	138,265	125,738	272,454	246,437
Operating profit	29,527	25,563	58,676	49,818
Industrial [Member]
Segment Reporting Information [Line Items]
Net sales	233,404	249,577	475,906	495,544
Net sales	233,404	249,577	475,906	495,538
Operating profit	27,430	38,316	48,931	70,694
Intersegment sales [Member]
Segment Reporting Information [Line Items]
Net sales	$ 0	$ (1)	$ 0	$ (6)

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

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Amount of the cost of borrowed funds accounted for as interest expense.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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