Revenue Recognition (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 29, 2019 segment	Sep. 29, 2019 item	Sep. 29, 2019 USD ($)	Sep. 30, 2018 USD ($)
Disaggregation of Revenue
Number of distribution channels | item				4
Number of geographic segments			3	3
Revenue	$ 394.7	$ 390.9			$ 1,200.2	$ 1,177.3
Wholesale
Disaggregation of Revenue
Revenue	239.3	235.0			729.9	713.0
OEM
Disaggregation of Revenue
Revenue	55.5	57.2			172.4	174.6
Specialty
Disaggregation of Revenue
Revenue	84.7	84.2			249.7	240.7
DIY
Disaggregation of Revenue
Revenue	15.2	14.5			48.2	49.0
Residential & commercial flow control
Disaggregation of Revenue
Revenue	202.7	195.8			622.7	601.3
HVAC & gas
Disaggregation of Revenue
Revenue	122.5	130.8			370.9	386.5
Drainage & water re-use
Disaggregation of Revenue
Revenue	43.5	42.2			129.8	122.5
Water quality
Disaggregation of Revenue
Revenue	26.0	22.1			76.8	67.0
Americas
Disaggregation of Revenue
Revenue	270.3	262.7			816.2	775.8
Americas | Wholesale
Disaggregation of Revenue
Revenue	152.1	146.7			459.8	433.9
Americas | OEM
Disaggregation of Revenue
Revenue	20.0	19.4			62.7	58.6
Americas | Specialty
Disaggregation of Revenue
Revenue	83.6	82.7			247.5	236.4
Americas | DIY
Disaggregation of Revenue
Revenue	14.6	13.9			46.2	46.9
Americas | Residential & commercial flow control
Disaggregation of Revenue
Revenue	151.0	144.4			459.7	435.3
Americas | HVAC & gas
Disaggregation of Revenue
Revenue	73.4	77.1			221.9	220.2
Americas | Drainage & water re-use
Disaggregation of Revenue
Revenue	20.7	19.8			60.4	55.2
Americas | Water quality
Disaggregation of Revenue
Revenue	25.2	21.4			74.2	65.1
Europe
Disaggregation of Revenue
Revenue	107.9	111.6			337.4	351.7
Europe | Wholesale
Disaggregation of Revenue
Revenue	72.2	73.5			226.9	234.7
Europe | OEM
Disaggregation of Revenue
Revenue	35.1	37.5			108.5	114.9
Europe | DIY
Disaggregation of Revenue
Revenue	0.6	0.6			2.0	2.1
Europe | Residential & commercial flow control
Disaggregation of Revenue
Revenue	41.1	40.2			130.1	132.2
Europe | HVAC & gas
Disaggregation of Revenue
Revenue	44.7	49.4			139.0	152.7
Europe | Drainage & water re-use
Disaggregation of Revenue
Revenue	21.5	21.7			66.4	65.9
Europe | Water quality
Disaggregation of Revenue
Revenue	0.6	0.3			1.9	0.9
APMEA
Disaggregation of Revenue
Revenue	16.5	16.6			46.6	49.8
APMEA | Wholesale
Disaggregation of Revenue
Revenue	15.0	14.8			43.2	44.4
APMEA | OEM
Disaggregation of Revenue
Revenue	0.4	0.3			1.2	1.1
APMEA | Specialty
Disaggregation of Revenue
Revenue	1.1	1.5			2.2	4.3
APMEA | Residential & commercial flow control
Disaggregation of Revenue
Revenue	10.6	11.2			32.9	33.8
APMEA | HVAC & gas
Disaggregation of Revenue
Revenue	4.4	4.3			10.0	13.6
APMEA | Drainage & water re-use
Disaggregation of Revenue
Revenue	1.3	0.7			3.0	1.4
APMEA | Water quality
Disaggregation of Revenue
Revenue	$ 0.2	$ 0.4			$ 0.7	$ 1.0