Summary of Significant Accounting Policies - Additional Information (Details) - Customer	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2017	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017	Dec. 30, 2017
Disclosure Summary Of Significant Accounting Policies [Line Items]
Extended product warranty period				1 year
Period to extend warranty, performance obligation		60 days		60 days
Products warranty period				2 years
Minimum
Disclosure Summary Of Significant Accounting Policies [Line Items]
Products warranty period				1 year
Maximum
Disclosure Summary Of Significant Accounting Policies [Line Items]
Products warranty period				2 years
IQ 532/577 Laser Consoles
Disclosure Summary Of Significant Accounting Policies [Line Items]
Products warranty period	5 years
Revenue, Total | Customer Concentration Risk
Disclosure Summary Of Significant Accounting Policies [Line Items]
Number of customers		1	0	0	0
Customer and supplier accounted percentage of total revenues, accounts receivable and purchases		10.00%	10.00%	10.00%	10.00%
Percentage of revenues accounted		11.00%
Accounts Receivable | Customer Concentration Risk
Disclosure Summary Of Significant Accounting Policies [Line Items]
Number of customers				1		0
Customer and supplier accounted percentage of total revenues, accounts receivable and purchases				10.00%		10.00%
Percentage of accounts receivable accounted				18.00%
Royalty Agreements
Disclosure Summary Of Significant Accounting Policies [Line Items]
Number of customers				2