Goodwill and Intangible Assets - Goodwill (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended		6 Months Ended		6 Months Ended		1 Months Ended
	Jun. 24, 2012	Dec. 25, 2011	Jun. 24, 2012 Public Safety and Security	Dec. 25, 2011 Public Safety and Security	Jun. 24, 2012 Kratos Government Solutions	Dec. 25, 2011 Kratos Government Solutions	Jun. 30, 2012 Discontinued operations Integral Systems, Inc.
Goodwill [Line Items]
Goodwill impairment charge associated with discontinued operations							$ 1.5
Goodwill, Access Of Fair Value Over Carrying Value, Percentage					7.40%
Goodwill [Roll Forward]
Balance as of December 25, 2011		571.9		33.0		538.9
Retrospective adjustments	(0.1)		0		(0.1)
Balance as of December 25, 2011 after retrospective adjusments	571.8		33.0		538.8
Additions due to business combinations	3.8		3.8		0
Balance as of June 24, 2012	575.6		36.8		538.8
Accumulated impairment losses	$ 165.4		$ 18.3	$ 18.3	$ 147.1	$ 165.4