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Employee Pension and Other Benefit Plans - Additional Information (Details) £ in Millions	12 Months Ended
	Jun. 27, 2020 USD ($)	Jun. 27, 2020 GBP (£)	Jun. 29, 2019 USD ($)	Jun. 29, 2019 GBP (£)	Jun. 30, 2018 USD ($)
Employee 401(k) Plans
Maximum contribution by an employee, as percentage of annual compensation	50.00%	50.00%
Maximum amount of contribution by an employee in a calendar year	$ 19,500
Employer match of employee's contributions of the first 3% of eligible compensation (as a percent)	100.00%	100.00%
Percentage of eligible compensation, matched 100% by employer	3.00%	3.00%
Employer match of employee's contributions of the next 2% of eligible compensation (as a percent)	50.00%	50.00%
Percentage of eligible compensation, matched 50% by employer	2.00%	2.00%
Company's matching contribution to the plan	$ 4,900,000		$ 4,900,000		$ 4,200,000
Employee Defined Benefit Plans
Required contributions expected in next fiscal year	$ 0
Minimum maturity period for investment in index-linked Gilts	5 years	5 years
Other Post Retirement Benefit Plans
Employee Defined Benefit Plans
Benefit obligation	$ 400,000		400,000
Pension Benefit Plans
Employee Defined Benefit Plans
Future amortization of losses	2,100,000
Benefit obligation	138,900,000		140,000,000.0		$ 136,700,000
Employer contributions	4,800,000		5,100,000
United Kingdom \| Pension Benefit Plans
Employee Defined Benefit Plans
Employer contributions	$ 600,000	£ 0.5	$ 600,000	£ 0.5