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Retirement Plans - Narrative (Details) £ in Thousands, $ in Thousands	3 Months Ended
	Jun. 25, 2021 USD ($)	Jun. 26, 2020 USD ($)	Jun. 25, 2021 GBP (£)	Mar. 26, 2021 USD ($)	Mar. 26, 2021 GBP (£)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 353	$ 240
Expected contributions in current fiscal year	$ 943
Other Defined Benefit Plans | Pension Promise
Defined Benefit Plan Disclosure [Line Items]
Retirement age	65 years
Other assets, net	$ 1,107		£ 703	$ 1,272	£ 928
Accrued retirement, other long-term liabilities	$ 1,107		£ 703	$ 1,272	£ 928
Defined Contribution Plan
Defined Benefit Plan Disclosure [Line Items]
Maximum employee contribution	50.00%
Employer matching contribution	100.00%
Maximum employer contribution	5.00%
Total contributions	$ 1,256	1,029
Defined Contribution Plan | 401(K) Plan
Defined Benefit Plan Disclosure [Line Items]
Maximum employee contribution	35.00%
Vesting percentage	100.00%
Defined Contribution Plan | AME Plan
Defined Benefit Plan Disclosure [Line Items]
Total contributions	$ 218	$ 179

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

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Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

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