Acquisitions and Dispositions - Acquisitions Narrative (Details) - USD ($) $ in Millions						3 Months Ended				9 Months Ended
		Jun. 30, 2015	Jan. 21, 2015	Oct. 08, 2014	Apr. 30, 2014	Sep. 26, 2015	Dec. 31, 2014	Sep. 27, 2014	Jun. 28, 2014	Sep. 26, 2015	Sep. 27, 2014
Business Acquisition [Line Items]
Net sales						$ 618.5		$ 642.9		$ 1,895.1	$ 1,909.3
Operating earnings (loss)						14.9		33.4		57.3	13.8
Goodwill	[1]					504.3	$ 474.3			504.3
Cost of products sold						442.5		452.9		1,354.2	1,355.4
Reznor
Business Acquisition [Line Items]
Business acquisition, cash paid					$ 260.0
Other payments to acquire businesses					2.6
Working capital and other post-closing adjustments							$ 0.7		$ 1.9
Goodwill expected to be tax deductible					76.1
Intangible assets acquired					125.0
Acquisition related costs											6.1
Net sales						35.5		38.0		109.0	61.8
Operating earnings (loss)						1.0		1.8		3.4	0.4
Depreciation and amortization						4.4		3.5		12.2	5.8
Cash and equivalents acquired					7.0
Fair value adjustment of inventory					1.8
Goodwill					$ 103.8
Cost of products sold								$ 0.3			$ 1.8
Phoenix Wholesale, Inc.
Business Acquisition [Line Items]
Business acquisition, cash paid				$ 13.9
Net sales						5.6				15.3
Operating earnings (loss)						(1.0)				(3.5)
Depreciation and amortization						0.3				0.8
Holdback amount				1.6
Consideration transferred to escrow				$ 1.0
Anthro
Business Acquisition [Line Items]
Business acquisition, cash paid			$ 50.8
Other payments to acquire businesses			0.2
Working capital and other post-closing adjustments						0.7
Intangible assets acquired			19.6
Net sales						12.5				29.2
Operating earnings (loss)						1.2				1.1
Depreciation and amortization						1.3				3.5
Consideration transferred to escrow			5.0
Total consideration			51.0			50.3
Fair value of tangible net assets acquired			5.2
Cash and equivalents acquired			0.6
Fair value adjustment of inventory			0.5
Goodwill			$ 25.5
Cost of products sold										0.5
Numera, Inc.
Business Acquisition [Line Items]
Business acquisition, cash paid		$ 12.0
Intangible assets acquired		11.0
Operating earnings (loss)						(1.1)				(1.1)
Depreciation and amortization						0.6				0.6
Consideration transferred to escrow		1.5
Total consideration		15.7
Goodwill		4.4
Additional payment contingent upon billing thresholds		28.0
Contingent consideration sales threshold		12.1
Contingent Consideration		3.7
Tangible net assets acquired		$ 0.3
Hardware revenue recognition period (in years)		3 years
Activations revenue recognition period (in years)		2 years
Deferred revenue						1.6				1.6
Capitalized direct and incremental costs						$ 1.2				$ 1.2

[1] The CAS and combined AVC reporting units did not have goodwill for any periods presented.