Retirement Plans - Defined Benefit Plans, Additional Information (Details) £ in Thousands, $ in Thousands	12 Months Ended
Mar. 26, 2021 USD ($)	Mar. 27, 2020 USD ($)	Mar. 26, 2021 GBP (£)	Mar. 27, 2020 GBP (£)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 986	$ 943
Company contributions next fiscal year	943
Other Defined Benefit Plan \| Pension Promise
Defined Benefit Plan Disclosure [Line Items]
Other assets, net	1,272	978	£ 928	£ 903
Accrued retirement, other long-term liabilities	$ 1,272	$ 978	£ 928	£ 903

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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