BUSINESS SEGMENTS - Changes in Goodwill (Detail) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Jun. 29, 2018	Dec. 28, 2018	Dec. 29, 2017	Dec. 30, 2016
Goodwill [Roll Forward]
Goodwill, Beginning Balance			$ 778.1	$ 764.6
Foreign currency translation			(19.3)	13.5
Acquisition related	[1]		73.2
Goodwill, Ending Balance			832.0	778.1	$ 764.6
Acquisitions of businesses, net of cash acquired		$ (150.1)	(150.1)	0.0	(4.7)
Preliminary net working capital adjustment		4.6
Working capital acquired		32.6
Intangible assets acquired		$ 60.6
Acquisition costs			2.6
Sales from acquired entities			71.9
Network and Security Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance			408.8	405.0
Foreign currency translation			(9.3)	3.8
Acquisition related	[1]		73.2
Goodwill, Ending Balance			472.7	408.8	405.0
Electrical and Electronic Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance			181.7	181.0
Foreign currency translation			(0.8)	0.7
Acquisition related	[1]		0.0
Goodwill, Ending Balance			180.9	181.7	181.0
Utility Power Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance			187.6	178.6
Foreign currency translation			(9.2)	9.0
Acquisition related	[1]		0.0
Goodwill, Ending Balance			$ 178.4	$ 187.6	$ 178.6

[1] In the second quarter of 2018, the Company completed the acquisition of security businesses in Australia and New Zealand for $150.1 million, including a preliminary net working capital adjustment of $4.6 million. The transaction was financed primarily from borrowings under the revolving lines of credit. The purchase price was preliminarily allocated to $32.6 million of working capital and $60.6 million of intangible assets. Acquisition costs were $2.6 million. The year ended 2018 results include approximately $71.9 million of sales from the acquired entities. The purchase price allocation is pending finalization, and is expected to be completed in early 2019.