Net Purchase Price and Preliminary Fair Values of Assets and Liabilities (Detail) (Micronetics, USD $) In Thousands, unless otherwise specified	Jun. 08, 2012
Micronetics
Consideration transferred
Cash paid to shareholders and to settle vested options	$ 69,830
Value allocated to unvested options	513
Less cash acquired	(2,109)
Net purchase price	68,234
Estimated fair value of tangible assets acquired and liabilities assumed
Cash	2,109
Accounts receivable	3,592
Inventory	12,080
Fixed assets	5,301
Other current and non-current assets	2,893
Accounts payable and accrued expenses	(6,014)
Long-term debt	(6,575)
Deferred taxes	(8,052)
Estimated fair value of net tangible assets acquired	5,334
Estimated fair value of identifiable intangible assets	18,500
Estimated fair value of goodwill	46,509
Estimated fair value of assets acquired	70,343
Less cash acquired	(2,109)
Net purchase price	$ 68,234

Business Acquisition, Cost of Acquired Entity, Cash Paid for Settlement of Acquiree Stock Options

No definition available.

Name:	mrcy_BusinessAcquisitionCostOfAcquiredEntityCashPaidForSettlementOfAcquireeStockOptions
Namespace Prefix:	mrcy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Business Acquisition Fair Value Of Unvested Employee Share Based Awards Assumed

+ References

No definition available.

+ Details

Name:	mrcy_BusinessAcquisitionFairValueOfUnvestedEmployeeShareBasedAwardsAssumed
Namespace Prefix:	mrcy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Business Acquisition Purchase Price Allocatioin Deferred Tax Asset

+ References

No definition available.

+ Details

Name:	mrcy_BusinessAcquisitionPurchasePriceAllocatioinDeferredTaxAsset
Namespace Prefix:	mrcy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Business Acquisition, Purchase Price Allocation, Accounts Payable and Accrued Liabilities

+ References

No definition available.

+ Details

Name:	mrcy_BusinessAcquisitionPurchasePriceAllocationAccountsPayableAndAccruedLiabilities
Namespace Prefix:	mrcy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents Acquired

+ References

No definition available.

+ Details

Name:	mrcy_BusinessAcquisitionPurchasePriceAllocationCurrentAssetsCashAndCashEquivalentsAcquired
Namespace Prefix:	mrcy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

+ Details

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

- Definition

The amount of acquisition cost of a business combination allocated to assets acquired.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Details

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

- Definition

The amount of cash and cash equivalents acquired in a business combination.

+ References

+ Details

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

- Definition

The amount of acquisition cost of a business combination allocated to inventory, including finished goods, work-in-process, and raw materials.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Definition

The amount of acquisition cost of a business combination allocated to receivables.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Definition

The amount of acquisition cost of a business combination allocated to the current portion of long-term debt of the acquired entity.

+ References

+ Details

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

- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 53

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Definition

Amount of acquisition cost of a business combination allocated to assets, excluding financial assets and goodwill, lacking physical substance.

+ References

No definition available.

+ Details

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

- Definition

The amount of acquisition cost of a business combination allocated to noncurrent assets.

+ References

+ Details

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

- Definition

Amount of acquisition cost of a business combination allocated to other assets not separately disclosed in the balance sheet.

+ References

No definition available.

+ Details

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

- Details

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

- Definition

The net amount recognized as of the acquisition date for the aggregate identifiable assets acquired in excess of or less than the aggregate liabilities assumed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=9154965&loc=d3e2207-128464

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph i

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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