Goodwill - Additional Information (Detail)	Mar. 31, 2013
Goodwill [Line Items]
Increase in discount rate cash flow analysis result in failure of interim goodwill impairment test	1.00%

Goodwill Impairment Test, Fair Value Assumptions, Increase (Decrease) In Discount Rate

No definition available.

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Namespace Prefix:	mrcy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant