Summary of Significant Accounting Policies - Accounts Receivable Factoring (Details) - USD ($) $ in Thousands |
12 Months Ended | ||||
|---|---|---|---|---|---|
Jul. 03, 2026 |
Jun. 27, 2025 |
Jun. 01, 2026 |
Dec. 10, 2025 |
Aug. 13, 2024 |
|
| Significant Accounting Policies [Line Items] | |||||
| Limit on purchased receivables | $ 100 | $ 75 | $ 60 | ||
| Receivables purchase agreement, term | 1 year | ||||
| Factored amount | $ 72,313 | $ 59,999 | |||
| Factoring fees | 1,709 | 1,758 | |||
| Location, Statement of Financial Position, Balance [Axis]: us-gaap:AccountsReceivableNetCurrent | |||||
| Significant Accounting Policies [Line Items] | |||||
| Factored amount | 71,922 | 52,164 | |||
| Location, Statement of Financial Position, Balance [Axis]: mrcy:DueToFactoringLiability | |||||
| Significant Accounting Policies [Line Items] | |||||
| Factored amount | $ 391 | $ 7,835 | |||