Debt Instrument, Term, Extension

No definition available.

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Namespace Prefix:	mrcy_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

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+ Details

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Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

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Balance Type:	debit
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- Definition

Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense.

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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

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+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

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+ Details

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

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- Details

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Balance Type:
Period Type:

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Debt (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
Debt (Details) - USD ($) $ in Thousands	Feb. 28, 2022	Dec. 26, 2025	Dec. 27, 2024	Dec. 26, 2025	Dec. 27, 2024	Nov. 04, 2025	Jun. 27, 2025
Debt Instrument [Line Items]
Outstanding borrowings		$ 591,500		$ 591,500			$ 591,500
Outstanding letter of credit		5,878		5,878
Interest expense		7,849	$ 8,430	15,735	$ 17,336
Deferred debt issuance cost, write-off				845
Debt instrument, term, extension						5 years
Revolving Credit Facility
Debt Instrument [Line Items]
Term of revolving credit facility	5 years
Maximum borrowing capacity		850,000		850,000		$ 850
Term Loan
Debt Instrument [Line Items]
Unamortized deferred financing costs		3,156		3,156
Debt issuance costs		$ 4,961		$ 4,961