Deferred Sales Commissions, Amortization Period Greater than One Year

No definition available.

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- Definition

Extended Product Warranty, Period

+ References

No definition available.

+ Details

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- Definition

Percentage of total revenue recognized under multiple-deliverable arrangements during the reporting periods.

+ References

No definition available.

+ Details

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- Definition

Product Warranty Period

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Revenue, Performance Obligation Satisfied over Time

+ References

No definition available.

+ Details

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Namespace Prefix:	mrcy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479837/606-10-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org/1943274/2147479837/606-10-45-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of consideration expected to be received as agent for product and service transferred to customer by another party, before deduction of payment for product and service provided by that party.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 38
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-38

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
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-Topic 606
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+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 03, 2026	Jun. 27, 2025	Jun. 28, 2024
Deferred Revenue Arrangement [Line Items]
Percentage of revenue recognized	46.00%
Deferred sales commission, amortization period greater than one year	$ 1,143	$ 627
Contract with customer, liability	151,055	127,605
Contract with customer, liability, revenue recognized		92,566
Revenue, remaining performance obligation, amount	1,082
Contract asset balances	285,760	$ 278,475
Gross Billing, Agent Transaction	459,846
Revenue, Performance Obligation Satisfied over Time	$ 467,131
Contract Accounting
Deferred Revenue Arrangement [Line Items]
Percentage of revenue recognized	53.00%	53.00%	45.00%
Transferred over Time
Deferred Revenue Arrangement [Line Items]
Percentage of revenue recognized	47.00%	47.00%	55.00%
Minimum
Deferred Revenue Arrangement [Line Items]
Product warranty period	12 months
Extended product warranty, period	12 months
Maximum
Deferred Revenue Arrangement [Line Items]
Product warranty period	36 months
Extended product warranty, period	36 months