Goodwill and Intangible Assets - Goodwill (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended		12 Months Ended		12 Months Ended		1 Months Ended
	Dec. 30, 2012	Dec. 25, 2011	Dec. 30, 2012 Public Safety & Security	Dec. 25, 2011 Public Safety & Security	Dec. 30, 2012 Kratos Government Solutions	Dec. 25, 2011 Kratos Government Solutions	Jun. 30, 2012 Discontinued operations Integral Systems, Inc.
Goodwill [Line Items]
Percentage by which goodwill fair value exceeded carrying value					7.40%
Goodwill impairment charge	$ 82.0		$ 0		$ 82.0		$ 1.5
Goodwill [Roll Forward]
Balance as of December 25, 2011		572.0		33.0		539.0
Retrospective adjustments	(0.4)		0		(0.4)
Balance as of December 25, 2011 after retrospective adjusments	571.6		33.0		538.6
Additions due to business combinations	106.9		2.6		104.3
Impairments	(82.0)		0		(82.0)		(1.5)
Balance as of December 30, 2012	596.5		35.6		560.9
Accumulated impairment losses		$ 247.4		$ 18.3		$ 229.1