Summary of Performance of Operations by Reportable Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Segment Reporting, Revenue Reconciling Item [Line Items]
Intersegment revenues	$ 0	$ 0
Net revenues	53,940	49,428
Adjusted EBITDA	3,619	1,638
Reportable Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net revenues to unaffiliated customers	53,940	49,428
Net revenues	53,940	49,428
Adjusted EBITDA	3,619	1,638
MCE \| Reportable Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net revenues to unaffiliated customers	43,488	31,897
Intersegment revenues	1,114	4,908
Net revenues	44,602	36,805
Adjusted EBITDA	2,343	(2,209)
Mercury Defense and Intelligence Systems \| Reportable Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net revenues to unaffiliated customers	11,130	15,827
Intersegment revenues		8
Net revenues	11,130	15,835
Adjusted EBITDA	1,358	3,223
Eliminations \| Reportable Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Net revenues to unaffiliated customers	(678)	1,704
Intersegment revenues	(1,114)	(4,916)
Net revenues	(1,792)	(3,212)
Adjusted EBITDA	$ (82)	$ 624

Tabular disclosure of adjusted EBITDA. Adjusted EBITDA is defined as earnings from continuing operations before interest income and expense, income taxes, depreciation, amortization of acquired intangible assets, restructuring, impairment of long-lived assets, acquisition costs and other related expenses, fair value adjustments from purchase accounting and stock-based compensation costs.

No definition available.

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- Definition

Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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- Definition

Amount of revenue from external customers for the reportable segment. Such disclosure is presented if the amount is: (a) included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 27

-Subparagraph a

-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.

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Amount of revenue from transactions with other operating segments of the same entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 27

-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.

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