Summary of Significant Accounting Policies - Warranty Activity (Details) - Warranty Reserves - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018
Movement in Extended Product Warranty Accrual [Roll Forward]
Balance at beginning of period	$ 36.4	$ 36.7
Amounts accrued	29.4	21.9
Warranties charged to accrual	(24.2)	(25.0)
Remeasurement of obligations under Topic 606			$ 2.8
Balance at end of period	41.6	36.4
Correction
Movement in Extended Product Warranty Accrual [Roll Forward]
Balance at beginning of period	$ 39.5
Balance at end of period		$ 39.5