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Retirement Plans - Narrative (Details) £ in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 24, 2021 USD ($)	Sep. 25, 2020 USD ($)	Sep. 24, 2021 USD ($)	Sep. 25, 2020 USD ($)	Sep. 24, 2021 GBP (£)	Mar. 26, 2021 USD ($)	Mar. 26, 2021 GBP (£)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 343	$ 247	$ 696	$ 487
Expected contributions in current fiscal year	943		$ 943
Other Defined Benefit Plans | Pension Promise
Defined Benefit Plan Disclosure [Line Items]
Retirement age			65 years
Other assets, net	1,087		$ 1,087		£ 797	$ 1,272	£ 928
Accrued retirement, other long-term liabilities	1,087		$ 1,087		£ 797	$ 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	1,089	1,040	$ 2,345	2,069
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	$ 211	$ 206	$ 429	$ 385

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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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