Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 24, 2012	Jun. 30, 2013 Segment	Jun. 24, 2012
Segment Reporting Information [Line Items]
Number of principal business segments			2
Service revenues	$ 110.2	$ 112.1	$ 226.2	$ 214.2
Product sales	125.0	107.7	262.3	215.1
Revenues	235.2	219.8	488.5	429.3
Depreciation and amortization	13.6	12.3	27.8	25.9
Operating income	8.9	7.4	20.3	16.5
Kratos Government Solutions
Segment Reporting Information [Line Items]
Service revenues	58.5	68.1	123.9	129.6
Product sales	125.0	107.7	262.3	215.1
Revenues	183.5	175.8	386.2	344.7
Depreciation and amortization	12.7	11.4	25.9	24.2
Operating income	5.3	8.8	17.4	18.4
Public Safety and Security
Segment Reporting Information [Line Items]
Service revenues	51.7	44.0	102.3	84.6
Product sales	0	0	0	0
Revenues	51.7	44.0	102.3	84.6
Depreciation and amortization	0.9	0.9	1.9	1.7
Operating income	2.7	2.8	3.9	4.0
Unallocated corporate expense, net
Segment Reporting Information [Line Items]
Operating income	$ 0.9	$ (4.2)	$ (1.0)	$ (5.9)