Acquisitions - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2015	Jun. 28, 2014	Jun. 27, 2015	Jun. 28, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners					19.90%
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests				$ (134.7)
Noncontrolling Interest, Ownership Percentage by Parent					80.10%
Payments to Acquire Businesses, Net of Cash Acquired	$ 96.0		$ 99.0	$ 0.0
Goodwill, Acquired During Period	46.5
Finite-lived Intangible Assets Acquired	53.3
Pentair Residential Filtration [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests		$ 134.3
Canada, Dollars
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	$ 120.5