Organization and Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 25, 2022	Dec. 26, 2021	Dec. 27, 2020
Disaggregation of Revenue [Line Items]
Total revenues	$ 898.3	$ 811.5	$ 747.7
Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total revenues	676.6	579.6
Kratos Government Solutions | U.S. Government
Disaggregation of Revenue [Line Items]
Total revenues	420.4	359.7
Kratos Government Solutions | International
Disaggregation of Revenue [Line Items]
Total revenues	157.5	151.5
Kratos Government Solutions | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total revenues	98.7	68.4
Kratos Government Solutions | Fixed price
Disaggregation of Revenue [Line Items]
Total revenues	476.1	447.3
Kratos Government Solutions | Cost plus fee
Disaggregation of Revenue [Line Items]
Total revenues	158.4	96.9
Kratos Government Solutions | Time and materials
Disaggregation of Revenue [Line Items]
Total revenues	42.1	35.4
Unmanned Systems
Disaggregation of Revenue [Line Items]
Total revenues	221.7	231.9
Unmanned Systems | U.S. Government
Disaggregation of Revenue [Line Items]
Total revenues	203.3	211.4
Unmanned Systems | International
Disaggregation of Revenue [Line Items]
Total revenues	15.6	18.3
Unmanned Systems | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total revenues	2.8	2.2
Unmanned Systems | Fixed price
Disaggregation of Revenue [Line Items]
Total revenues	156.6	151.4
Unmanned Systems | Cost plus fee
Disaggregation of Revenue [Line Items]
Total revenues	59.1	78.1
Unmanned Systems | Time and materials
Disaggregation of Revenue [Line Items]
Total revenues	$ 6.0	$ 2.4