Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013 Segment	Sep. 30, 2012
Segment Reporting Information [Line Items]
Number of principal business segments			2
Service revenues	$ 108.8	$ 125.6	$ 335.0	$ 339.8
Product sales	117.6	150.7	379.9	365.8
Revenues	226.4	276.3	714.9	705.6
Depreciation and amortization	12.9	16.6	40.7	42.5
Operating income	6.1	14.1	26.4	30.6
Kratos Government Solutions
Segment Reporting Information [Line Items]
Service revenues	57.0	72.8	180.9	202.4
Product sales	117.6	150.7	379.9	365.8
Revenues	174.6	223.5	560.8	568.2
Depreciation and amortization	12.1	15.7	38.0	39.9
Operating income	6.4	14.0	23.8	32.4
Public Safety and Security
Segment Reporting Information [Line Items]
Service revenues	51.8	52.8	154.1	137.4
Product sales	0	0	0	0
Revenues	51.8	52.8	154.1	137.4
Depreciation and amortization	0.8	0.9	2.7	2.6
Operating income	1.8	3.3	5.7	7.3
Unallocated corporate expense, net
Segment Reporting Information [Line Items]
Operating income	$ (2.1)	$ (3.2)	$ (3.1)	$ (9.1)