Goodwill and Intangibles Finite-Lived Intangibles (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Oct. 02, 2021	Sep. 26, 2020	Oct. 02, 2021	Sep. 26, 2020	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 443.8	$ 416.3	$ 443.8	$ 416.3	$ 417.7	$ 415.0
Acquisitions			26.9
Goodwill, Other Increase (Decrease)			(0.8)	1.3
Gross Amount	893.2	871.2	893.2	871.2	872.4
Accumulated Amortization	(344.0)	(311.6)	(344.0)	(311.6)	(320.1)
Amortization Expense for Intangibles	8.3	8.0	24.3	24.0
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	173.0	165.8	173.0	165.8	166.2
Accumulated Amortization	0.0	0.0	0.0	0.0	0.0
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	701.7	687.0	701.7	687.0	687.7
Accumulated Amortization	(329.9)	(298.2)	(329.9)	(298.2)	(306.4)
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	18.5	18.4	18.5	18.4	18.5
Accumulated Amortization	(14.1)	(13.4)	(14.1)	(13.4)	(13.7)
Propulsion [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	14.9	14.5	14.9	14.5	15.3	14.5
Acquisitions			0.0
Goodwill, Other Increase (Decrease)			(0.4)	0.0
Gross Amount	1.0	1.0	1.0	1.0	1.0
Accumulated Amortization	(0.5)	(0.5)	(0.5)	(0.5)	(0.5)
Parts and Accessories [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	379.4	371.9	379.4	371.9	372.5	371.9
Acquisitions			7.1
Goodwill, Other Increase (Decrease)			(0.2)	0.0
Gross Amount	637.3	617.6	637.3	617.6	618.8
Accumulated Amortization	(134.8)	(104.5)	(134.8)	(104.5)	(112.4)
Boat [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	49.5	29.9	49.5	29.9	29.9	$ 28.6
Acquisitions			19.8
Goodwill, Other Increase (Decrease)			(0.2)	1.3
Gross Amount	254.9	252.6	254.9	252.6	252.6
Accumulated Amortization	$ (208.7)	$ (206.6)	$ (208.7)	$ (206.6)	$ (207.2)

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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