Quarterly Financial Information (unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information (unaudited)
Revenue	$ 400.3	$ 394.7	$ 416.8	$ 388.7	$ 387.6	$ 390.9	$ 407.9	$ 378.5	$ 1,600.5	$ 1,564.9	$ 1,456.7
Gross profit	170.1	168.6	174.6	164.2	165.9	164.5	169.4	156.7	677.5	656.5	602.4
Net income (loss)	$ 31.8	$ 32.3	$ 36.4	$ 31.0	$ 32.3	$ 31.5	$ 36.0	$ 28.2	$ 131.5	$ 128.0	$ 73.1
BASIC EPS
Net income (in dollars per share)	$ 0.94	$ 0.95	$ 1.06	$ 0.91	$ 0.94	$ 0.92	$ 1.05	$ 0.82	$ 3.86	$ 3.73	$ 2.12
DILUTED EPS
Net income (in dollars per share)	0.93	0.94	1.06	0.91	0.94	0.92	1.05	0.82	3.85	3.73	2.12
Dividends declared per common share (in dollars per share)	$ 0.23	$ 0.23	$ 0.23	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.19	$ 0.90	$ 0.82	$ 0.75