Acquisitions - Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Business Acquisition [Line Items]
Pro forma net income attributable to Kratos	$ (0.7)	$ 3.9	$ (0.9)	$ 7.0
FTT
Business Acquisition [Line Items]
Pro forma revenues			356.4
Pro forma net income before tax			5.1
Pro forma net income			6.5
Pro forma net income attributable to Kratos			$ 6.3
Basic pro forma income per share attributable to Kratos (USD per share)			$ 0.06
Diluted pro forma income per share attributable to Kratos (USD per share)			$ 0.06