Cost Method Investment and Collaborative Arrangement (Details) - USD ($) $ in Thousands	3 Months Ended												9 Months Ended	12 Months Ended			36 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Oct. 01, 2016	Sep. 30, 2017	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016	Dec. 30, 2017
Schedule of Cost-method Investments [Line Items]
Ownership interest percentage																22.70%
Gross investments amount												$ 6,000
Short-term loan to cost-method investee										$ 1,000	$ 1,000		$ 2,000	$ 2,000	$ 0	$ 0
Cost method investments, fair value									$ 2,300					2,300			$ 2,300
Impairment of cost-basis investment														(1,761)	(1,459)	(492)
Decrease of cost method investment																	3,700
Movements In Cost Method Investments [Roll Forward]
Beginning balance								$ 2,288					$ 4,049	4,049	4,508
Investment made during fiscal year												$ 1,000		0	1,000	5,000
Impairment of cost-basis investment														(1,761)	(1,459)	(492)
Ending balance									2,288					2,288	$ 4,049	$ 4,508	2,288
Maximum loss exposure amount									2,900					2,900			2,900
Prepaid royalties									600					$ 600			$ 600
Payments for royalties									$ 625
Forecast
Movements In Cost Method Investments [Roll Forward]
Payments for royalties	$ 1,250	$ 1,250	$ 1,250	$ 1,250	$ 875	$ 875	$ 875	$ 875