BUSINESS SEGMENTS - Segment Information (Detail) - USD ($) $ in Millions		3 Months Ended																12 Months Ended
		Dec. 29, 2017		Sep. 29, 2017	[2]	Jun. 30, 2017	[3]	Mar. 31, 2017	[4]	Dec. 30, 2016		Sep. 30, 2016	[6]	Jul. 01, 2016	[7]	Apr. 01, 2016	[8]	Dec. 29, 2017	Dec. 30, 2016	Jan. 01, 2016
Segment Reporting Information [Line Items]
Net sales		$ 2,013.8	[1]	$ 2,016.4		$ 2,001.4		$ 1,895.8		$ 1,894.6	[5]	$ 1,956.3		$ 1,955.7		$ 1,816.2		$ 7,927.4	$ 7,622.8	$ 6,190.5
Operating income		80.4	[1]	$ 81.0		$ 82.7		$ 69.0		81.0	[5]	$ 87.3		$ 56.7		$ 60.3		313.1	285.3	267.8
Depreciation																		28.2	27.9	23.8
Amortization of intangible assets																		36.1	37.6	25.4
Total assets		4,252.2								4,093.6								4,252.2	4,093.6
Capital expenditures																		41.1	32.6	28.6
Network and Security Solutions [Member]
Segment Reporting Information [Line Items]
Net sales																		4,114.4	4,083.8	3,968.2
Operating income																		262.6	275.8	258.2
Depreciation																		3.1	3.2	3.6
Amortization of intangible assets																		14.4	14.1	14.7
Total assets		1,947.1								1,974.0								1,947.1	1,974.0	1,902.8
Capital expenditures																		3.7	3.4	3.0
Electrical and Electronic Solutions [Member]
Segment Reporting Information [Line Items]
Net sales																		2,225.5	2,103.2	1,816.5	[9]
Operating income																		114.3	97.5	121.1	[9]
Depreciation																		2.4	2.7	1.4	[9]
Amortization of intangible assets																		8.4	8.5	6.3	[9]
Total assets		1,068.3								983.6								1,068.3	983.6	1,071.4	[9]
Capital expenditures																		1.9	2.9	1.0	[9]
Utility Power Solutions [Member]
Segment Reporting Information [Line Items]
Net sales																		1,587.5	1,435.8	405.8	[9]
Operating income																		73.1	56.7	22.4	[9]
Depreciation																		3.9	4.2	1.2	[9]
Amortization of intangible assets																		13.3	15.0	3.9	[9]
Total assets		871.4								821.9								871.4	821.9	813.4	[9]
Capital expenditures																		1.7	2.5	0.8	[9]
Corporate [Member]
Segment Reporting Information [Line Items]
Net sales	[10]																	0.0	0.0	0.0
Operating income	[10]																	(136.9)	(144.7)	(133.9)
Depreciation	[10]																	18.8	17.8	16.0
Amortization of intangible assets	[10]																	0.0	0.0	0.0
Total assets	[10]	365.4								313.9								365.4	313.9	350.6
Capital expenditures	[10]																	33.8	23.8	21.9
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Net sales																		7,927.4	7,622.8	6,190.5
Operating income																		313.1	285.3	267.8
Depreciation																		28.2	27.9	22.2
Amortization of intangible assets																		36.1	37.6	24.9
Total assets		$ 4,252.2								$ 4,093.4								4,252.2	4,093.4	4,138.2
Capital expenditures																		$ 41.1	$ 32.6	$ 26.7

[1] In the fourth quarter of 2017, "Operating income" includes $9.0 million of intangible asset amortization, $1.5 million of acquisition and integration costs and an intangible asset impairment charge of $5.7 million.

[2] In the third quarter of 2017, "Operating income" includes $9.1 million of intangible asset amortization and $0.8 million of acquisition and integration costs.

[3] In the second quarter of 2017, "Operating income" includes $9.0 million of intangible asset amortization

[4] In the first quarter of 2017, "Operating income" includes $9.0 million of intangible asset amortization

[5] In the fourth quarter of 2016, "Operating income" includes $9.0 million of intangible asset amortization and $0.8 million of acquisition and integration costs.

[6] In the third quarter of 2016, "Operating income" includes $9.4 million of intangible asset amortization, $0.7 million of acquisition and integration costs and a restructuring reversal of $0.2 million.

[7] In the second quarter of 2016, "Operating income" includes $9.5 million of intangible asset amortization, $5.6 million of restructuring charges, $7.6 million of Latin America bad debt provision, $1.4 million of acquisition and integration costs and $9.6 million related to a settlement of pension obligation in the UK.

[8] In the first quarter of 2016, "Operating income" includes $9.7 million of intangible asset amortization and $2.2 million of acquisition and integration costs.

[9] At the beginning of the fourth quarter of 2015, the Company acquired Power Solutions which is reported in both the EES and UPS business segments. For further information, see Note 3. "Business Combinations".

[10] Corporate "Total assets" primarily consists of cash and cash equivalents, deferred tax assets, and corporate fixed assets.