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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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