Organization and Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 26, 2021	Dec. 27, 2020	Dec. 29, 2019
Disaggregation of Revenue [Line Items]
Total revenues	$ 811.5	$ 747.7	$ 717.5
Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total revenues	579.6	560.7
Kratos Government Solutions | U.S. Government
Disaggregation of Revenue [Line Items]
Total revenues	359.7	375.9
Kratos Government Solutions | International
Disaggregation of Revenue [Line Items]
Total revenues	151.5	123.8
Kratos Government Solutions | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total revenues	68.4	61.0
Kratos Government Solutions | Fixed price
Disaggregation of Revenue [Line Items]
Total revenues	447.3	437.6
Kratos Government Solutions | Cost plus fee
Disaggregation of Revenue [Line Items]
Total revenues	96.9	89.1
Kratos Government Solutions | Time and materials
Disaggregation of Revenue [Line Items]
Total revenues	35.4	34.0
Unmanned Systems
Disaggregation of Revenue [Line Items]
Total revenues	231.9	187.0
Unmanned Systems | U.S. Government
Disaggregation of Revenue [Line Items]
Total revenues	211.4	170.5
Unmanned Systems | International
Disaggregation of Revenue [Line Items]
Total revenues	18.3	15.7
Unmanned Systems | U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total revenues	2.2	0.8
Unmanned Systems | Fixed price
Disaggregation of Revenue [Line Items]
Total revenues	151.4	126.9
Unmanned Systems | Cost plus fee
Disaggregation of Revenue [Line Items]
Total revenues	78.1	57.1
Unmanned Systems | Time and materials
Disaggregation of Revenue [Line Items]
Total revenues	$ 2.4	$ 3.0