Business Segment Information (Reconciliation of Total Operating Profit) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Total operating profit from segments	$ 128,211	$ 123,596
Income from operations	110,228	103,561
Operating Segments
Segment Reporting Information [Line Items]
Total operating profit from segments	128,211	123,596
Corporate
Segment Reporting Information [Line Items]
Corporate overhead expenses	$ (17,983)	$ (20,035)

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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