CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (1.9)	$ 2.4	$ 0.9	$ 1.4
Change in cumulative translation adjustment	(0.9)	0.9	(0.1)	0.8
Comprehensive income (loss)	(2.8)	3.3	0.8	2.2
Less: Comprehensive income (loss) attributable to noncontrolling interest	0.5	0.0	0.3	(0.1)
Comprehensive income (loss) attributable to Kratos	$ (3.3)	$ 3.3	$ 0.5	$ 2.3