Segment Information - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 29, 2024 USD ($) segment	Dec. 31, 2023 USD ($)	Dec. 25, 2022 USD ($)
Segment Reporting Information [Line Items]
Number of reportable (in segments) | segment	2
Total revenues	$ 1,136.3	$ 1,037.1	$ 898.3
Kratos Government Solutions
Segment Reporting Information [Line Items]
Total revenues	865.8	824.9	676.6
Assets of foreign subsidiaries	223.2	204.6	178.3
Non-US
Segment Reporting Information [Line Items]
Total revenues	$ 226.6	$ 202.0	$ 173.1
Percentage of foreign revenue to total revenue (percent)	20.00%	19.00%	19.00%