Intangible Assets - Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization of acquired intangible assets	$ 17,967	$ 31,909	$ 34,320
Research and development
Finite-Lived Intangible Assets [Line Items]
Amortization of acquired intangible assets	277	569	745
Amortization of acquired intangible assets
Finite-Lived Intangible Assets [Line Items]
Amortization of acquired intangible assets	$ 17,690	$ 31,340	$ 33,575