Summary of Significant Accounting Policies and Other Information - Narrative (Details) $ in Thousands, € in Millions		3 Months Ended			12 Months Ended
	Jan. 17, 2018 USD ($)	Dec. 29, 2018 USD ($)	Sep. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)	Dec. 29, 2018 USD ($) unit	Jan. 17, 2018 USD ($)	Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 29, 2018 EUR (€)	Dec. 29, 2018 USD ($)	Dec. 30, 2017 EUR (€)	Dec. 30, 2017 USD ($)	Oct. 01, 2017
Summary of Significant Accounting Policies and Other Information [Line Items]
Investments in equity securities										$ 10,312		$ 10,993
Gain from equity method investments					$ (700)
Equity method investments										11,600
Cost method investments										7,900
Number of reporting units | unit					7
Foreign exchange (gain) loss					$ 863		$ (2,376)	$ (472)
Loss contingency accrual									€ 1.1	1,300	€ 0.9	1,100
Provisional estimate of Tax Act				$ 47,000
Preliminary estimate of toll charge				49,000			49,000
Other net tax benefits				(2,000)
Income taxes					40,377		84,518	18,786
TCJA one-time charge		$ 3,200		$ 49,000
Toll charge, noncurrent		28,800
ASU 2016-01
Summary of Significant Accounting Policies and Other Information [Line Items]
Cumulative effect adjustment					(9,800)
Gain recognized on statement of income					700
ASU 2016-02
Summary of Significant Accounting Policies and Other Information [Line Items]
Estimated recognition of right-of-use assets and lease liabilities for operating leases										27,000
Selling, General and Administrative Expenses
Summary of Significant Accounting Policies and Other Information [Line Items]
Advertising expense					2,800			2,900
Shipping and handling fees and costs					$ 12,300		$ 10,900	9,100
Industrial
Summary of Significant Accounting Policies and Other Information [Line Items]
Impairment of intangible assets								6,000
Patents, licenses and software
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					11 years 4 months 24 days		11 years 146 days
Distribution network
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					12 years 7 months 6 days		12 years 36 days
Customer relationships | Industrial
Summary of Significant Accounting Policies and Other Information [Line Items]
Impairment of intangible assets								2,200
Trade Name | Industrial
Summary of Significant Accounting Policies and Other Information [Line Items]
Impairment of intangible assets								3,800
Electronics Non Silicon Unit [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Excess fair value over carrying value													175.60%
Electronics (Silicon) Unit [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Excess fair value over carrying value													79.80%
Passenger Car [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Excess fair value over carrying value													233.00%
Commercial Vehicle Products
Summary of Significant Accounting Policies and Other Information [Line Items]
Excess fair value over carrying value													202.10%
Sensors [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Excess fair value over carrying value													63.10%
Relay Unit [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Excess fair value over carrying value													113.80%
Fuse Unit [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Excess fair value over carrying value													370.00%
Custom Products Reporting Unit [Member] | Industrial
Summary of Significant Accounting Policies and Other Information [Line Items]
Impairment of intangible assets								6,000
Custom Products Reporting Unit [Member] | Customer relationships | Industrial
Summary of Significant Accounting Policies and Other Information [Line Items]
Impairment of intangible assets								2,200
Custom Products Reporting Unit [Member] | Trade Name | Industrial
Summary of Significant Accounting Policies and Other Information [Line Items]
Impairment of intangible assets								$ 3,800
Minimum | Trademarks and tradenames
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					5 years
Minimum | Patents, licenses and software
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					5 years
Minimum | Distribution network
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					3 years
Maximum | Trademarks and tradenames
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					20 years
Maximum | Patents, licenses and software
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					17 years
Maximum | Distribution network
Summary of Significant Accounting Policies and Other Information [Line Items]
Weighted Average Useful Life (Years)					20 years
Building
Summary of Significant Accounting Policies and Other Information [Line Items]
Useful life					21 years
Equipment | Minimum
Summary of Significant Accounting Policies and Other Information [Line Items]
Useful life					7 years
Equipment | Maximum
Summary of Significant Accounting Policies and Other Information [Line Items]
Useful life					10 years
Furniture and Fixtures [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Useful life					7 years
Tools, Dies and Molds [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Useful life					5 years
Computer Equipment [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Useful life					3 years
Other Noncurrent Assets [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Marketable securities										$ 9,100		8,000
ATEC
Summary of Significant Accounting Policies and Other Information [Line Items]
Ownership percentage									24.00%	24.00%
EB Tech
Summary of Significant Accounting Policies and Other Information [Line Items]
Ownership percentage									20.00%	20.00%
Powersem
Summary of Significant Accounting Policies and Other Information [Line Items]
Ownership percentage									45.00%	45.00%
Polytronics [Member]
Summary of Significant Accounting Policies and Other Information [Line Items]
Investments in equity securities									€ 8.9	$ 10,200	€ 9.2	$ 11,000
Ownership percentage									7.20%	7.20%
Toll Charge
Summary of Significant Accounting Policies and Other Information [Line Items]
TCJA one-time charge		2,300
Other Items
Summary of Significant Accounting Policies and Other Information [Line Items]
TCJA one-time charge		900
IXYS Corporation | Toll Charge
Summary of Significant Accounting Policies and Other Information [Line Items]
TCJA one-time charge	$ 7,000	$ (1,000)	$ (2,000)			$ 7,000