Gross amount of long-lived physical assets disposed during the reporting period.

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Lease Term, Option to Renew

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Sale Leaseback Transaction, Lease Term

+ References

No definition available.

+ Details

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

- Definition

The number of lease term renewal option related to the sale-leaseback transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	mrcy_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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

- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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

Name:	us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of the gain recorded in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller to be recognized in future periods.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 25

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6456126&loc=d3e49567-112750

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Property and Equipment - Additional Information (Detail) $ in Thousands			12 Months Ended
	Jun. 27, 2013 USD ($)	Apr. 20, 2007 USD ($) OptionPlan	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2013 USD ($)
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense related to property and equipment			$ 6,332	$ 7,625	$ 8,445
Loss on sale of building			0	0	$ 1,091
Lease term		10 years
Number of five year term option to renew \| OptionPlan		2
Lease term, option to renew		5 years
Deferred gain on sale-leaseback transaction		$ 11,569
Computer equipment and software
Property, Plant and Equipment [Line Items]
Retirement of asset			$ 733	$ 715
Restructuring and Other Charges
Property, Plant and Equipment [Line Items]
Loss on sale of building	$ 1,091