Basis of Presentation - Schedule of Revision of Prior Period Financial Statements - Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 28, 2019	Dec. 29, 2018	Dec. 31, 2017
Assets
Accounts receivable, net	$ 372,356	$ 400,663	$ 241,880
Total current assets	724,850	720,277
Total assets	1,016,816	978,106
Liabilities and shareholders’ equity
Accrued customer rebates and returns	88,575	96,888	6,522
Total current liabilities	195,552	232,139
Total liabilities and shareholders' equity	$ 1,016,816	978,106
ASU 2014-09 [Member]
Assets
Accounts receivable, net			337,417
Liabilities and shareholders’ equity
Accrued customer rebates and returns			102,059
As Previously Reported [Member] | ASU 2014-09 [Member]
Assets
Accounts receivable, net		310,114
Total current assets		629,728
Total assets		887,557
Liabilities and shareholders’ equity
Accrued customer rebates and returns		6,339
Total current liabilities		141,590
Total liabilities and shareholders' equity		887,557
Adjustment [Member] | ASU 2014-09 [Member]
Assets
Accounts receivable, net		90,549	95,537
Total current assets		90,549
Total assets		90,549
Liabilities and shareholders’ equity
Accrued customer rebates and returns		90,549	$ 95,537
Total current liabilities		90,549
Total liabilities and shareholders' equity		$ 90,549