ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - Accounts Receivable and Advertising (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for doubtful accounts receivable	$ 1.3
Advertising expense	42.9	$ 39.0	$ 27.5
Prepaid advertising	$ 0.9	$ 0.4
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable uncollateralized customer obligations trading days	30 days
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable uncollateralized customer obligations trading days	90 days