Acquisition Acquisition - Selected Unaudited Pro-forma Combined Statement of Earnings (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition, Pro Forma Information [Abstract]
Revenues	$ 223.8	$ 236.2	$ 188.4	$ 178.5	$ 215.5	$ 196.0	$ 164.4	$ 168.3	$ 826.9	$ 744.2	$ 755.7
Earnings (Loss)	$ 79.4	$ (17.8)	$ 4.4	$ (0.4)	$ 31.9	$ 10.5	$ (30.9)	$ (5.0)	$ 65.6	$ 6.5	$ 19.8
Per Share - Basic	$ 0.88	$ (0.20)	$ 0.05	$ 0	$ 0.36	$ 0.12	$ (0.35)	$ (0.06)	$ 0.73	$ 0.07	$ 0.22
Per Share - Diluted	$ 0.87	$ (0.20)	$ 0.05	$ 0	$ 0.35	$ 0.12	$ (0.35)	$ (0.06)	$ 0.72	$ 0.07	$ 0.22
Compex Corporation [Member]
Business Acquisition, Pro Forma Information [Abstract]
Pro-forma									$ 827.5	$ 755.7
Pro-forma									$ 66.3	$ 7.4
Pro-forma									$ 0.74	$ 0.08
Pro-forma									$ 0.73	$ 0.08

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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