Segment information - Sales and Adjusted EBITDA by Reporting Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Segment Reporting Information
Net sales	$ 576.5	$ 809.9	$ 1,286.6	$ 1,614.8
Adjusted EBITDA	83.2	165.4	204.0	330.9
Power Transmission
Segment Reporting Information
Net sales	370.0	501.5	811.2	1,001.0
Adjusted EBITDA	57.7	105.6	137.2	215.5
Fluid Power
Segment Reporting Information
Net sales	206.5	308.4	475.4	613.8
Adjusted EBITDA	$ 25.5	$ 59.8	$ 66.8	$ 115.4