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Segment Information (Details) $ in Millions	3 Months Ended
Segment Information (Details) $ in Millions	Mar. 29, 2020 USD ($) item	Mar. 29, 2020 USD ($)	Mar. 29, 2020 USD ($) segment	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment information
Number of geographic segments	3		3
Revenue		$ 382.6		$ 388.7
Consolidated operating income (loss)		47.8		46.7
Interest income		(0.1)		(0.1)
Interest expense		3.0		3.6
Other expense, net		0.3		0.5
INCOME BEFORE INCOME TAXES		44.6		42.7
Capital Expenditures		8.9		6.9
Depreciation and Amortization		11.4		11.4
Identifiable assets (at end of period)	$ 1,767.4	1,767.4	$ 1,767.4	1,683.4	$ 1,723.1
Property, plant and equipment, net (at end of period)	201.8	201.8	201.8	199.6	$ 200.0
Residential & Commercial Flow Control
Segment information
Revenue		197.7		203.5
HVAC & Gas Products
Segment information
Revenue		113.6		119.3
Drainage & Water Re-use Products
Segment information
Revenue		42.7		40.5
Water Quality Products
Segment information
Revenue		28.6		25.4
U.S.
Segment information
Property, plant and equipment, net (at end of period)	117.2	117.2	117.2	110.3
Reportable segments
Segment information
Consolidated operating income (loss)		57.0		57.6
Corporate
Segment information
Consolidated operating income (loss)		(9.2)		(10.9)
Intersegment sales
Segment information
Revenue		20.1		23.4
Americas
Segment information
Revenue		262.4		258.9
Capital Expenditures		6.6		3.9
Depreciation and Amortization		7.4		7.1
Identifiable assets (at end of period)	1,155.4	1,155.4	1,155.4	1,050.1
Property, plant and equipment, net (at end of period)	121.0	121.0	121.0	114.3
Americas \| Residential & Commercial Flow Control
Segment information
Revenue		148.7		147.4
Americas \| HVAC & Gas Products
Segment information
Revenue		67.6		68.7
Americas \| Drainage & Water Re-use Products
Segment information
Revenue		18.5		18.1
Americas \| Water Quality Products
Segment information
Revenue		27.6		24.7
Americas \| U.S.
Segment information
Revenue		246.7		243.5
Americas \| Reportable segments
Segment information
Consolidated operating income (loss)		43.4		43.1
Americas \| Intersegment sales
Segment information
Revenue		2.4		2.9
Europe
Segment information
Revenue		110.2		116.3
Capital Expenditures		2.2		3.0
Depreciation and Amortization		3.4		3.6
Identifiable assets (at end of period)	519.6	519.6	519.6	524.9
Property, plant and equipment, net (at end of period)	75.4	75.4	75.4	78.7
Europe \| Residential & Commercial Flow Control
Segment information
Revenue		41.0		45.4
Europe \| HVAC & Gas Products
Segment information
Revenue		44.4		48.5
Europe \| Drainage & Water Re-use Products
Segment information
Revenue		23.9		21.9
Europe \| Water Quality Products
Segment information
Revenue		0.9		0.5
Europe \| Reportable segments
Segment information
Consolidated operating income (loss)		13.7		13.2
Europe \| Intersegment sales
Segment information
Revenue		4.1		3.6
APMEA
Segment information
Revenue		10.0		13.5
Capital Expenditures		0.1
Depreciation and Amortization		0.6		0.7
Identifiable assets (at end of period)	92.4	92.4	92.4	108.4
Property, plant and equipment, net (at end of period)	$ 5.4	5.4	$ 5.4	6.6
APMEA \| Residential & Commercial Flow Control
Segment information
Revenue		8.0		10.7
APMEA \| HVAC & Gas Products
Segment information
Revenue		1.6		2.1
APMEA \| Drainage & Water Re-use Products
Segment information
Revenue		0.3		0.5
APMEA \| Water Quality Products
Segment information
Revenue		0.1		0.2
APMEA \| Reportable segments
Segment information
Consolidated operating income (loss)		(0.1)		1.3
APMEA \| Intersegment sales
Segment information
Revenue		$ 13.6		$ 16.9