Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Mar. 30, 2014
Revenues:
Service revenues	$ 87.4us-gaap_SalesRevenueServicesNet	$ 100.6us-gaap_SalesRevenueServicesNet
Product sales	95.1us-gaap_SalesRevenueGoodsNet	99.5us-gaap_SalesRevenueGoodsNet
Total revenues	182.5us-gaap_SalesRevenueNet	200.1us-gaap_SalesRevenueNet
Depreciation & amortization:
Total depreciation and amortization	8.5	9.6
Operating income (loss):
Total operating income (loss)	(1.5)us-gaap_OperatingIncomeLoss	3.3us-gaap_OperatingIncomeLoss
Unallocated corporate expense, net
Operating income (loss):
Total operating income (loss)	(2.2)	(1.8)
Kratos Government Solutions
Revenues:
Service revenues	49.8	51.7
Product sales	82.7	79.8
Total revenues	132.5	131.5
Depreciation & amortization:
Total depreciation and amortization	6.8	7.6
Operating income (loss):
Total operating income (loss)	4.7	5.9
Public Safety & Security
Revenues:
Service revenues	37.6	48.9
Product sales	0	0
Total revenues	37.6	48.9
Depreciation & amortization:
Total depreciation and amortization	0.1	0.5
Operating income (loss):
Total operating income (loss)	0.1	1.0
Unmanned Systems
Revenues:
Service revenues	0	0
Product sales	12.4	19.7
Total revenues	12.4	19.7
Depreciation & amortization:
Total depreciation and amortization	1.6	1.5
Operating income (loss):
Total operating income (loss)	$ (4.1)	$ (1.8)

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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