ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - Balance sheet (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	$ 75,856	$ 59,328
Inventory	181,354	145,423
Prepaid expenses and other current assets	17,762	12,211
Deferred charges and other assets	1,478	1,014
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accrued expenses and other current liabilities	44,575	53,022
Taxes payable	1,766	6,390
Accumulated deficit	(215,533)	$ (240,104)
Impact of Adoption
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	(7,522)
Inventory	2,825
Prepaid expenses and other current assets	(751)
Deferred charges and other assets	19
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accrued expenses and other current liabilities	(751)
Taxes payable	(1,132)
Accumulated deficit	(3,546)
Balances without Adoption of ASC 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable, net	68,334
Inventory	184,179
Prepaid expenses and other current assets	17,011
Deferred charges and other assets	1,497
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accrued expenses and other current liabilities	43,824
Taxes payable	634
Accumulated deficit	$ (219,079)