Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 28, 2026	Jun. 29, 2025	Jun. 28, 2026	Jun. 29, 2025
Disaggregation of Revenue [Line Items]
Total Revenues	$ 458.8	$ 351.5	$ 829.8	$ 654.1
Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	379.7	278.3	668.1	517.8
Kratos Government Solutions \| U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	249.2	186.7	429.1	336.1
Kratos Government Solutions \| International
Disaggregation of Revenue [Line Items]
Total Revenues	84.3	52.2	154.9	107.5
Kratos Government Solutions \| U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	46.2	39.4	84.1	74.2
Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	79.1	73.2	161.7	136.3
Unmanned Systems \| U.S. Government
Disaggregation of Revenue [Line Items]
Total Revenues	69.2	62.0	144.0	118.1
Unmanned Systems \| International
Disaggregation of Revenue [Line Items]
Total Revenues	5.6	9.0	11.4	14.8
Unmanned Systems \| U.S. Commercial and other customers
Disaggregation of Revenue [Line Items]
Total Revenues	4.3	2.2	6.3	3.4
Fixed price \| Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	256.6	170.3	470.8	336.8
Fixed price \| Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	52.0	59.2	107.9	111.8
Cost plus fee \| Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	109.2	94.8	168.3	152.8
Cost plus fee \| Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	25.1	13.1	50.1	22.9
Time and materials \| Kratos Government Solutions
Disaggregation of Revenue [Line Items]
Total Revenues	13.9	13.2	29.0	28.2
Time and materials \| Unmanned Systems
Disaggregation of Revenue [Line Items]
Total Revenues	$ 2.0	$ 0.9	$ 3.7	$ 1.6