INCOME TAXES - Reconciliation of Income Tax Rates (Details)	6 Months Ended	12 Months Ended
Jan. 03, 2020	Jun. 28, 2019	Jun. 29, 2018	Jun. 30, 2017
Income Tax Disclosure [Abstract]
U.S. statutory income tax rate	21.00%	21.00%	28.10%	35.00%
State taxes	1.40%	2.40%	1.90%	1.00%
International income	0.90%	(0.50%)	(0.50%)	(1.30%)
Research and development tax credit	(4.70%)	(4.50%)	(2.90%)	(2.00%)
Foreign derived intangibles income deduction	(0.80%)	(1.30%)	0.00%	0.00%
Change in valuation allowance	(4.80%)	(1.80%)	0.20%	(0.20%)
U.S. production activity benefit	0.00%	0.00%	(0.90%)	(0.50%)
Equity-based compensation	(5.40%)	(2.10%)	(1.80%)	(2.60%)
Settlement of tax audits	0.00%	0.00%	(2.20%)	0.00%
U.S. tax reform	0.00%	0.00%	0.40%	0.00%
Other items	0.40%	1.20%	0.40%	(0.10%)
Effective income tax rate	8.00%	14.40%	22.70%	29.30%

Effective Income Tax Rate Reconciliation, Deduction, Foreign Derived Intangibles Income, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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