Revenue Recognition (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019 segment	Mar. 31, 2019 item	Mar. 31, 2019 USD ($)	Apr. 01, 2018 USD ($)
Disaggregation of Revenue
Number of distribution channels | item		4
Number of geographic segments	3	3
Revenue			$ 388.7	$ 378.5
Wholesale
Disaggregation of Revenue
Revenue			237.7	233.2
OEM
Disaggregation of Revenue
Revenue			57.3	59.1
Specialty
Disaggregation of Revenue
Revenue			76.5	67.6
DIY
Disaggregation of Revenue
Revenue			17.2	18.6
Residential & commercial flow control
Disaggregation of Revenue
Revenue			203.5	196.6
HVAC & gas
Disaggregation of Revenue
Revenue			119.3	120.7
Drainage & water re-use
Disaggregation of Revenue
Revenue			40.5	38.4
Water quality
Disaggregation of Revenue
Revenue			25.4	22.8
Americas
Disaggregation of Revenue
Revenue			258.9	241.1
Americas | Wholesale
Disaggregation of Revenue
Revenue			145.6	136.6
Americas | OEM
Disaggregation of Revenue
Revenue			20.8	19.1
Americas | Specialty
Disaggregation of Revenue
Revenue			76.1	67.6
Americas | DIY
Disaggregation of Revenue
Revenue			16.4	17.8
Americas | Residential & commercial flow control
Disaggregation of Revenue
Revenue			147.4	139.9
Americas | HVAC & gas
Disaggregation of Revenue
Revenue			68.7	62.5
Americas | Drainage & water re-use
Disaggregation of Revenue
Revenue			18.1	16.5
Americas | Water quality
Disaggregation of Revenue
Revenue			24.7	22.2
Europe
Disaggregation of Revenue
Revenue			116.3	123.0
Europe | Wholesale
Disaggregation of Revenue
Revenue			79.5	82.7
Europe | OEM
Disaggregation of Revenue
Revenue			36.0	39.5
Europe | DIY
Disaggregation of Revenue
Revenue			0.8	0.8
Europe | Residential & commercial flow control
Disaggregation of Revenue
Revenue			45.4	47.2
Europe | HVAC & gas
Disaggregation of Revenue
Revenue			48.5	53.9
Europe | Drainage & water re-use
Disaggregation of Revenue
Revenue			21.9	21.6
Europe | Water quality
Disaggregation of Revenue
Revenue			0.5	0.3
APMEA
Disaggregation of Revenue
Revenue			13.5	14.4
APMEA | Wholesale
Disaggregation of Revenue
Revenue			12.6	13.9
APMEA | OEM
Disaggregation of Revenue
Revenue			0.5	0.5
APMEA | Specialty
Disaggregation of Revenue
Revenue			0.4
APMEA | Residential & commercial flow control
Disaggregation of Revenue
Revenue			10.7	9.5
APMEA | HVAC & gas
Disaggregation of Revenue
Revenue			2.1	4.3
APMEA | Drainage & water re-use
Disaggregation of Revenue
Revenue			0.5	0.3
APMEA | Water quality
Disaggregation of Revenue
Revenue			$ 0.2	$ 0.3